diff --git a/lib/types/message-types.js b/lib/types/message-types.js
index 1bf1b9033..6d79fd076 100644
--- a/lib/types/message-types.js
+++ b/lib/types/message-types.js
@@ -1,517 +1,517 @@
 // @flow
 
 import invariant from 'invariant';
 
 import type { FetchResultInfoInterface } from '../utils/fetch-json';
 import { type ClientDBMediaInfo } from './media-types';
 import type {
   AddMembersMessageData,
   AddMembersMessageInfo,
   RawAddMembersMessageInfo,
 } from './messages/add-members';
 import type {
   ChangeRoleMessageData,
   ChangeRoleMessageInfo,
   RawChangeRoleMessageInfo,
 } from './messages/change-role';
 import type {
   ChangeSettingsMessageData,
   ChangeSettingsMessageInfo,
   RawChangeSettingsMessageInfo,
 } from './messages/change-settings';
 import type {
   CreateEntryMessageData,
   CreateEntryMessageInfo,
   RawCreateEntryMessageInfo,
 } from './messages/create-entry';
 import type {
   CreateSidebarMessageData,
   CreateSidebarMessageInfo,
   RawCreateSidebarMessageInfo,
 } from './messages/create-sidebar';
 import type {
   CreateSubthreadMessageData,
   CreateSubthreadMessageInfo,
   RawCreateSubthreadMessageInfo,
 } from './messages/create-subthread';
 import type {
   CreateThreadMessageData,
   CreateThreadMessageInfo,
   RawCreateThreadMessageInfo,
 } from './messages/create-thread';
 import type {
   DeleteEntryMessageData,
   DeleteEntryMessageInfo,
   RawDeleteEntryMessageInfo,
 } from './messages/delete-entry';
 import type {
   EditEntryMessageData,
   EditEntryMessageInfo,
   RawEditEntryMessageInfo,
 } from './messages/edit-entry';
 import type {
   ImagesMessageData,
   ImagesMessageInfo,
   RawImagesMessageInfo,
 } from './messages/images';
 import type {
   JoinThreadMessageData,
   JoinThreadMessageInfo,
   RawJoinThreadMessageInfo,
 } from './messages/join-thread';
 import type {
   LeaveThreadMessageData,
   LeaveThreadMessageInfo,
   RawLeaveThreadMessageInfo,
 } from './messages/leave-thread';
 import type {
   MediaMessageData,
   MediaMessageInfo,
   RawMediaMessageInfo,
 } from './messages/media';
 import type {
   RawRemoveMembersMessageInfo,
   RemoveMembersMessageData,
   RemoveMembersMessageInfo,
 } from './messages/remove-members';
 import type {
   RawRestoreEntryMessageInfo,
   RestoreEntryMessageData,
   RestoreEntryMessageInfo,
 } from './messages/restore-entry';
 import type {
   RawTextMessageInfo,
   TextMessageData,
   TextMessageInfo,
 } from './messages/text';
 import type {
   RawUnsupportedMessageInfo,
   UnsupportedMessageInfo,
 } from './messages/unsupported';
 import type {
   RawUpdateRelationshipMessageInfo,
   UpdateRelationshipMessageData,
   UpdateRelationshipMessageInfo,
 } from './messages/update-relationship';
 import { type RelativeUserInfo, type UserInfos } from './user-types';
 
 export const messageTypes = Object.freeze({
   TEXT: 0,
   CREATE_THREAD: 1,
   ADD_MEMBERS: 2,
   CREATE_SUB_THREAD: 3,
   CHANGE_SETTINGS: 4,
   REMOVE_MEMBERS: 5,
   CHANGE_ROLE: 6,
   LEAVE_THREAD: 7,
   JOIN_THREAD: 8,
   CREATE_ENTRY: 9,
   EDIT_ENTRY: 10,
   DELETE_ENTRY: 11,
   RESTORE_ENTRY: 12,
   // When the server has a message to deliver that the client can't properly
   // render because the client is too old, the server will send this message
   // type instead. Consequently, there is no MessageData for UNSUPPORTED - just
   // a RawMessageInfo and a MessageInfo. Note that native/persist.js handles
   // converting these MessageInfos when the client is upgraded.
   UNSUPPORTED: 13,
   IMAGES: 14,
   MULTIMEDIA: 15,
   UPDATE_RELATIONSHIP: 16,
   SIDEBAR_SOURCE: 17,
   CREATE_SIDEBAR: 18,
 });
 export type MessageType = $Values<typeof messageTypes>;
 export function assertMessageType(ourMessageType: number): MessageType {
   invariant(
     ourMessageType === 0 ||
       ourMessageType === 1 ||
       ourMessageType === 2 ||
       ourMessageType === 3 ||
       ourMessageType === 4 ||
       ourMessageType === 5 ||
       ourMessageType === 6 ||
       ourMessageType === 7 ||
       ourMessageType === 8 ||
       ourMessageType === 9 ||
       ourMessageType === 10 ||
       ourMessageType === 11 ||
       ourMessageType === 12 ||
       ourMessageType === 13 ||
       ourMessageType === 14 ||
       ourMessageType === 15 ||
       ourMessageType === 16 ||
       ourMessageType === 17 ||
       ourMessageType === 18,
     'number is not MessageType enum',
   );
   return ourMessageType;
 }
 
 const composableMessageTypes = new Set([
   messageTypes.TEXT,
   messageTypes.IMAGES,
   messageTypes.MULTIMEDIA,
 ]);
 export function isComposableMessageType(ourMessageType: MessageType): boolean {
   return composableMessageTypes.has(ourMessageType);
 }
 export function assertComposableMessageType(
   ourMessageType: MessageType,
 ): MessageType {
   invariant(
     isComposableMessageType(ourMessageType),
     'MessageType is not composed',
   );
   return ourMessageType;
 }
 export function assertComposableRawMessage(
   message: RawMessageInfo,
 ): RawComposableMessageInfo {
   invariant(
     message.type === messageTypes.TEXT ||
       message.type === messageTypes.IMAGES ||
       message.type === messageTypes.MULTIMEDIA,
     'Message is not composable',
   );
   return message;
 }
 export function messageDataLocalID(messageData: MessageData): ?string {
   if (
     messageData.type !== messageTypes.TEXT &&
     messageData.type !== messageTypes.IMAGES &&
     messageData.type !== messageTypes.MULTIMEDIA
   ) {
     return null;
   }
   return messageData.localID;
 }
 
 const mediaMessageTypes = new Set([
   messageTypes.IMAGES,
   messageTypes.MULTIMEDIA,
 ]);
 export function isMediaMessageType(ourMessageType: MessageType): boolean {
   return mediaMessageTypes.has(ourMessageType);
 }
 export function assetMediaMessageType(
   ourMessageType: MessageType,
 ): MessageType {
   invariant(isMediaMessageType(ourMessageType), 'MessageType is not media');
   return ourMessageType;
 }
 
 // *MessageData = passed to createMessages function to insert into database
 // Raw*MessageInfo = used by server, and contained in client's local store
 // *MessageInfo = used by client in UI code
 
 export type SidebarSourceMessageData = {
   +type: 17,
   +threadID: string,
   +creatorID: string,
   +time: number,
   +sourceMessage?: RawComposableMessageInfo | RawRobotextMessageInfo,
 };
 export type MessageData =
   | TextMessageData
   | CreateThreadMessageData
   | AddMembersMessageData
   | CreateSubthreadMessageData
   | ChangeSettingsMessageData
   | RemoveMembersMessageData
   | ChangeRoleMessageData
   | LeaveThreadMessageData
   | JoinThreadMessageData
   | CreateEntryMessageData
   | EditEntryMessageData
   | DeleteEntryMessageData
   | RestoreEntryMessageData
   | ImagesMessageData
   | MediaMessageData
   | UpdateRelationshipMessageData
   | SidebarSourceMessageData
   | CreateSidebarMessageData;
 
 export type MultimediaMessageData = ImagesMessageData | MediaMessageData;
 
 export type RawMultimediaMessageInfo =
   | RawImagesMessageInfo
   | RawMediaMessageInfo;
 export type RawComposableMessageInfo =
   | RawTextMessageInfo
   | RawMultimediaMessageInfo;
 
 export type RawRobotextMessageInfo =
   | RawCreateThreadMessageInfo
   | RawAddMembersMessageInfo
   | RawCreateSubthreadMessageInfo
   | RawChangeSettingsMessageInfo
   | RawRemoveMembersMessageInfo
   | RawChangeRoleMessageInfo
   | RawLeaveThreadMessageInfo
   | RawJoinThreadMessageInfo
   | RawCreateEntryMessageInfo
   | RawEditEntryMessageInfo
   | RawDeleteEntryMessageInfo
   | RawRestoreEntryMessageInfo
   | RawUpdateRelationshipMessageInfo
   | RawCreateSidebarMessageInfo
   | RawUnsupportedMessageInfo;
 export type RawSidebarSourceMessageInfo = {
   ...SidebarSourceMessageData,
   id: string,
 };
 export type RawMessageInfo =
   | RawComposableMessageInfo
   | RawRobotextMessageInfo
   | RawSidebarSourceMessageInfo;
 
 export type LocallyComposedMessageInfo =
   | ({
       ...RawImagesMessageInfo,
       +localID: string,
     } & RawImagesMessageInfo)
   | ({
       ...RawMediaMessageInfo,
       +localID: string,
     } & RawMediaMessageInfo)
   | ({
       ...RawTextMessageInfo,
       +localID: string,
     } & RawTextMessageInfo);
 
 export type MultimediaMessageInfo = ImagesMessageInfo | MediaMessageInfo;
 export type ComposableMessageInfo = TextMessageInfo | MultimediaMessageInfo;
 
 export type RobotextMessageInfo =
   | CreateThreadMessageInfo
   | AddMembersMessageInfo
   | CreateSubthreadMessageInfo
   | ChangeSettingsMessageInfo
   | RemoveMembersMessageInfo
   | ChangeRoleMessageInfo
   | LeaveThreadMessageInfo
   | JoinThreadMessageInfo
   | CreateEntryMessageInfo
   | EditEntryMessageInfo
   | DeleteEntryMessageInfo
   | RestoreEntryMessageInfo
   | UnsupportedMessageInfo
   | UpdateRelationshipMessageInfo
   | CreateSidebarMessageInfo;
 export type PreviewableMessageInfo =
   | RobotextMessageInfo
   | MultimediaMessageInfo;
 export type SidebarSourceMessageInfo = {
   +type: 17,
   +id: string,
   +threadID: string,
   +creator: RelativeUserInfo,
   +time: number,
   +sourceMessage: ComposableMessageInfo | RobotextMessageInfo,
 };
 
 export type MessageInfo =
   | ComposableMessageInfo
   | RobotextMessageInfo
   | SidebarSourceMessageInfo;
 
 export type ThreadMessageInfo = {
   messageIDs: string[],
   startReached: boolean,
   lastNavigatedTo: number, // millisecond timestamp
   lastPruned: number, // millisecond timestamp
 };
 
 // Tracks client-local information about a message that hasn't been assigned an
 // ID by the server yet. As soon as the client gets an ack from the server for
 // this message, it will clear the LocalMessageInfo.
 export type LocalMessageInfo = {
   +sendFailed?: boolean,
 };
 
 export type MessageStore = {
   +messages: { +[id: string]: RawMessageInfo },
   +threads: { +[threadID: string]: ThreadMessageInfo },
   +local: { +[id: string]: LocalMessageInfo },
   +currentAsOf: number,
 };
 
 export type RemoveMessageOperation = {
   +type: 'remove',
   +payload: { +ids: $ReadOnlyArray<string> },
 };
 
 export type RemoveMessagesForThreadsOperation = {
   +type: 'remove_messages_for_threads',
   +payload: { +threadIDs: $ReadOnlyArray<string> },
 };
 
 export type ReplaceMessageOperation = {
   +type: 'replace',
   +payload: { +id: string, +messageInfo: RawMessageInfo },
 };
 
 export type RekeyMessageOperation = {
   +type: 'rekey',
   +payload: { +from: string, +to: string },
 };
 
 export type RemoveAllMessagesOperation = {
   +type: 'remove_all',
 };
 
 export type ClientDBMessageInfo = {
   +id: string,
   +local_id: ?string,
   +thread: string,
   +user: string,
   +type: string,
   +future_type: ?string,
   +content: ?string,
   +time: string,
   +media_infos: ?$ReadOnlyArray<ClientDBMediaInfo>,
 };
 
 export type ClientDBReplaceMessageOperation = {
   +type: 'replace',
   +payload: ClientDBMessageInfo,
 };
 
 export type MessageStoreOperation =
   | RemoveMessageOperation
   | ReplaceMessageOperation
   | RekeyMessageOperation
   | RemoveMessagesForThreadsOperation
   | RemoveAllMessagesOperation;
 
 export type ClientDBMessageStoreOperation =
   | RemoveMessageOperation
   | ClientDBReplaceMessageOperation
   | RekeyMessageOperation
   | RemoveMessagesForThreadsOperation
   | RemoveAllMessagesOperation;
 
 export const messageTruncationStatus = Object.freeze({
   // EXHAUSTIVE means we've reached the start of the thread. Either the result
   // set includes the very first message for that thread, or there is nothing
   // behind the cursor you queried for. Given that the client only ever issues
   // ranged queries whose range, when unioned with what is in state, represent
   // the set of all messages for a given thread, we can guarantee that getting
   // EXHAUSTIVE means the start has been reached.
   EXHAUSTIVE: 'exhaustive',
   // TRUNCATED is rare, and means that the server can't guarantee that the
   // result set for a given thread is contiguous with what the client has in its
   // state. If the client can't verify the contiguousness itself, it needs to
   // replace its Redux store's contents with what it is in this payload.
   //  1) getMessageInfosSince: Result set for thread is equal to max, and the
   //     truncation status isn't EXHAUSTIVE (ie. doesn't include the very first
   //     message).
-  //  2) getMessageInfos: ThreadSelectionCriteria does not specify cursors, the
+  //  2) getMessageInfos: MessageSelectionCriteria does not specify cursors, the
   //     result set for thread is equal to max, and the truncation status isn't
   //     EXHAUSTIVE. If cursors are specified, we never return truncated, since
   //     the cursor given us guarantees the contiguousness of the result set.
   // Note that in the reducer, we can guarantee contiguousness if there is any
   // intersection between messageIDs in the result set and the set currently in
   // the Redux store.
   TRUNCATED: 'truncated',
   // UNCHANGED means the result set is guaranteed to be contiguous with what the
   // client has in its state, but is not EXHAUSTIVE. Basically, it's anything
   // that isn't either EXHAUSTIVE or TRUNCATED.
   UNCHANGED: 'unchanged',
 });
 export type MessageTruncationStatus = $Values<typeof messageTruncationStatus>;
 export function assertMessageTruncationStatus(
   ourMessageTruncationStatus: string,
 ): MessageTruncationStatus {
   invariant(
     ourMessageTruncationStatus === 'truncated' ||
       ourMessageTruncationStatus === 'unchanged' ||
       ourMessageTruncationStatus === 'exhaustive',
     'string is not ourMessageTruncationStatus enum',
   );
   return ourMessageTruncationStatus;
 }
 export type MessageTruncationStatuses = {
   [threadID: string]: MessageTruncationStatus,
 };
 
 export type ThreadCursors = { +[threadID: string]: ?string };
 
-export type ThreadSelectionCriteria = {
+export type MessageSelectionCriteria = {
   +threadCursors?: ?ThreadCursors,
   +joinedThreads?: ?boolean,
 };
 
 export type FetchMessageInfosRequest = {
   +cursors: ThreadCursors,
   +numberPerThread?: ?number,
 };
 export type FetchMessageInfosResponse = {
   +rawMessageInfos: $ReadOnlyArray<RawMessageInfo>,
   +truncationStatuses: MessageTruncationStatuses,
   +userInfos: UserInfos,
 };
 export type FetchMessageInfosResult = {
   +rawMessageInfos: $ReadOnlyArray<RawMessageInfo>,
   +truncationStatuses: MessageTruncationStatuses,
 };
 export type FetchMessageInfosPayload = {
   +threadID: string,
   +rawMessageInfos: $ReadOnlyArray<RawMessageInfo>,
   +truncationStatus: MessageTruncationStatus,
 };
 export type MessagesResponse = {
   +rawMessageInfos: $ReadOnlyArray<RawMessageInfo>,
   +truncationStatuses: MessageTruncationStatuses,
   +currentAsOf: number,
 };
 export const defaultNumberPerThread = 20;
 
 export type SendMessageResponse = {
   +newMessageInfo: RawMessageInfo,
 };
 export type SendMessageResult = {
   +id: string,
   +time: number,
   +interface: FetchResultInfoInterface,
 };
 export type SendMessagePayload = {
   +localID: string,
   +serverID: string,
   +threadID: string,
   +time: number,
   +interface: FetchResultInfoInterface,
 };
 
 export type SendTextMessageRequest = {
   +threadID: string,
   +localID?: string,
   +text: string,
 };
 export type SendMultimediaMessageRequest = {
   +threadID: string,
   +localID: string,
   +mediaIDs: $ReadOnlyArray<string>,
 };
 
 // Used for the message info included in log-in type actions
 export type GenericMessagesResult = {
   +messageInfos: RawMessageInfo[],
   +truncationStatus: MessageTruncationStatuses,
   +watchedIDsAtRequestTime: $ReadOnlyArray<string>,
   +currentAsOf: number,
 };
 
 export type SaveMessagesPayload = {
   +rawMessageInfos: $ReadOnlyArray<RawMessageInfo>,
   +updatesCurrentAsOf: number,
 };
 
 export type NewMessagesPayload = {
   +messagesResult: MessagesResponse,
 };
 
 export type MessageStorePrunePayload = {
   +threadIDs: $ReadOnlyArray<string>,
 };
diff --git a/server/src/creators/update-creator.js b/server/src/creators/update-creator.js
index a3ad73869..046af8817 100644
--- a/server/src/creators/update-creator.js
+++ b/server/src/creators/update-creator.js
@@ -1,794 +1,794 @@
 // @flow
 
 import invariant from 'invariant';
 
 import { nonThreadCalendarFilters } from 'lib/selectors/calendar-filter-selectors';
 import {
   keyForUpdateData,
   keyForUpdateInfo,
   rawUpdateInfoFromUpdateData,
 } from 'lib/shared/update-utils';
 import {
   type RawEntryInfo,
   type FetchEntryInfosBase,
   type CalendarQuery,
   defaultCalendarQuery,
 } from 'lib/types/entry-types';
 import {
   defaultNumberPerThread,
   type FetchMessageInfosResult,
 } from 'lib/types/message-types';
 import {
   type UpdateTarget,
   redisMessageTypes,
   type NewUpdatesRedisMessage,
 } from 'lib/types/redis-types';
 import type { RawThreadInfo } from 'lib/types/thread-types';
 import {
   type ServerUpdateInfo,
   type UpdateData,
   type RawUpdateInfo,
   type CreateUpdatesResult,
   updateTypes,
 } from 'lib/types/update-types';
 import type {
   UserInfos,
   LoggedInUserInfo,
   OldLoggedInUserInfo,
 } from 'lib/types/user-types';
 import { promiseAll } from 'lib/utils/promises';
 
 import { dbQuery, SQL, mergeAndConditions } from '../database/database';
 import type { SQLStatementType } from '../database/types';
 import { deleteUpdatesByConditions } from '../deleters/update-deleters';
 import {
   fetchEntryInfos,
   fetchEntryInfosByID,
 } from '../fetchers/entry-fetchers';
 import { fetchMessageInfos } from '../fetchers/message-fetchers';
 import {
   fetchThreadInfos,
   type FetchThreadInfosResult,
 } from '../fetchers/thread-fetchers';
 import {
   fetchKnownUserInfos,
   fetchCurrentUserInfo,
 } from '../fetchers/user-fetchers';
 import type { Viewer } from '../session/viewer';
 import { channelNameForUpdateTarget, publisher } from '../socket/redis';
 import createIDs from './id-creator';
 
 export type UpdatesForCurrentSession =
   // This is the default if no Viewer is passed, or if an isSocket Viewer is
   // passed in. We will broadcast to all valid sessions via Redis and return
   // nothing to the caller, relying on the current session's Redis listener to
   // pick up the updates and deliver them asynchronously.
   | 'broadcast'
   // This is the default if a non-isSocket Viewer is passed in. We avoid
   // broadcasting the update to the current session, and instead return the
   // update to the caller, who will handle delivering it to the client.
   | 'return'
   // This means we ignore any updates destined for the current session.
   // Presumably the caller knows what they are doing and has a different way of
   // communicating the relevant information to the client.
   | 'ignore';
 
 type DeleteCondition = {
   +userID: string,
   +target: ?string,
   +types: 'all_types' | $ReadOnlySet<number>,
 };
 
 export type ViewerInfo =
   | {
       viewer: Viewer,
       calendarQuery?: ?CalendarQuery,
       updatesForCurrentSession?: UpdatesForCurrentSession,
     }
   | {
       viewer: Viewer,
       calendarQuery: ?CalendarQuery,
       updatesForCurrentSession?: UpdatesForCurrentSession,
       threadInfos: { +[id: string]: RawThreadInfo },
     };
 const defaultUpdateCreationResult = { viewerUpdates: [], userInfos: {} };
 const sortFunction = (
   a: UpdateData | ServerUpdateInfo,
   b: UpdateData | ServerUpdateInfo,
 ) => a.time - b.time;
 const deleteUpdatesBatchSize = 500;
 
 // Creates rows in the updates table based on the inputed updateDatas. Returns
 // UpdateInfos pertaining to the provided viewerInfo, as well as related
 // UserInfos. If no viewerInfo is provided, no UpdateInfos will be returned. And
 // the update row won't have an updater column, meaning no session will be
 // excluded from the update.
 async function createUpdates(
   updateDatas: $ReadOnlyArray<UpdateData>,
   passedViewerInfo?: ?ViewerInfo,
 ): Promise<CreateUpdatesResult> {
   if (updateDatas.length === 0) {
     return defaultUpdateCreationResult;
   }
 
   // viewer.session will throw for a script Viewer
   let viewerInfo = passedViewerInfo;
   if (
     viewerInfo &&
     (viewerInfo.viewer.isScriptViewer || !viewerInfo.viewer.loggedIn)
   ) {
     viewerInfo = null;
   }
 
   const sortedUpdateDatas = [...updateDatas].sort(sortFunction);
 
   const filteredUpdateDatas: UpdateData[] = [];
   const keyedUpdateDatas: Map<string, UpdateData[]> = new Map();
   for (const updateData of sortedUpdateDatas) {
     const key = keyForUpdateData(updateData);
     if (!key) {
       filteredUpdateDatas.push(updateData);
       continue;
     }
     const conditionKey = `${updateData.userID}|${key}`;
 
     const deleteCondition = getDeleteCondition(updateData);
     invariant(
       deleteCondition,
       `updateData of type ${updateData.type} has conditionKey ` +
         `${conditionKey} but no deleteCondition`,
     );
 
     const curUpdateDatas = keyedUpdateDatas.get(conditionKey);
     if (!curUpdateDatas) {
       keyedUpdateDatas.set(conditionKey, [updateData]);
       continue;
     }
 
     const filteredCurrent = curUpdateDatas.filter(curUpdateData =>
       filterOnDeleteCondition(curUpdateData, deleteCondition),
     );
     if (filteredCurrent.length === 0) {
       keyedUpdateDatas.set(conditionKey, [updateData]);
       continue;
     }
 
     const isNewUpdateDataFiltered = !filteredCurrent.every(curUpdateData => {
       const curDeleteCondition = getDeleteCondition(curUpdateData);
       invariant(
         curDeleteCondition,
         `updateData of type ${curUpdateData.type} is in keyedUpdateDatas ` +
           "but doesn't have a deleteCondition",
       );
       return filterOnDeleteCondition(updateData, curDeleteCondition);
     });
     if (!isNewUpdateDataFiltered) {
       filteredCurrent.push(updateData);
     }
     keyedUpdateDatas.set(conditionKey, filteredCurrent);
   }
 
   for (const keyUpdateDatas of keyedUpdateDatas.values()) {
     filteredUpdateDatas.push(...keyUpdateDatas);
   }
   const ids = await createIDs('updates', filteredUpdateDatas.length);
 
   let updatesForCurrentSession =
     viewerInfo && viewerInfo.updatesForCurrentSession;
   if (!updatesForCurrentSession && viewerInfo) {
     updatesForCurrentSession = viewerInfo.viewer.isSocket
       ? 'broadcast'
       : 'return';
   } else if (!updatesForCurrentSession) {
     updatesForCurrentSession = 'broadcast';
   }
   const dontBroadcastSession =
     updatesForCurrentSession !== 'broadcast' && viewerInfo
       ? viewerInfo.viewer.session
       : null;
 
   const publishInfos: Map<string, PublishInfo> = new Map();
   const viewerRawUpdateInfos: RawUpdateInfo[] = [];
   const insertRows: (?(number | string))[][] = [];
   const earliestTime: Map<string, number> = new Map();
   for (let i = 0; i < filteredUpdateDatas.length; i++) {
     const updateData = filteredUpdateDatas[i];
     let content;
     if (updateData.type === updateTypes.DELETE_ACCOUNT) {
       content = JSON.stringify({ deletedUserID: updateData.deletedUserID });
     } else if (updateData.type === updateTypes.UPDATE_THREAD) {
       content = JSON.stringify({ threadID: updateData.threadID });
     } else if (updateData.type === updateTypes.UPDATE_THREAD_READ_STATUS) {
       const { threadID, unread } = updateData;
       content = JSON.stringify({ threadID, unread });
     } else if (
       updateData.type === updateTypes.DELETE_THREAD ||
       updateData.type === updateTypes.JOIN_THREAD
     ) {
       const { threadID } = updateData;
       content = JSON.stringify({ threadID });
     } else if (updateData.type === updateTypes.BAD_DEVICE_TOKEN) {
       const { deviceToken } = updateData;
       content = JSON.stringify({ deviceToken });
     } else if (updateData.type === updateTypes.UPDATE_ENTRY) {
       const { entryID } = updateData;
       content = JSON.stringify({ entryID });
     } else if (updateData.type === updateTypes.UPDATE_CURRENT_USER) {
       // user column contains all the info we need to construct the UpdateInfo
       content = null;
     } else if (updateData.type === updateTypes.UPDATE_USER) {
       const { updatedUserID } = updateData;
       content = JSON.stringify({ updatedUserID });
     } else {
       invariant(false, `unrecognized updateType ${updateData.type}`);
     }
 
     const target = getTargetFromUpdateData(updateData);
     const rawUpdateInfo = rawUpdateInfoFromUpdateData(updateData, ids[i]);
 
     if (!target || !dontBroadcastSession || target !== dontBroadcastSession) {
       const updateTarget = target
         ? { userID: updateData.userID, sessionID: target }
         : { userID: updateData.userID };
       const channelName = channelNameForUpdateTarget(updateTarget);
       let publishInfo = publishInfos.get(channelName);
       if (!publishInfo) {
         publishInfo = { updateTarget, rawUpdateInfos: [] };
         publishInfos.set(channelName, publishInfo);
       }
       publishInfo.rawUpdateInfos.push(rawUpdateInfo);
     }
 
     if (
       updatesForCurrentSession === 'return' &&
       viewerInfo &&
       updateData.userID === viewerInfo.viewer.id &&
       (!target || target === viewerInfo.viewer.session)
     ) {
       viewerRawUpdateInfos.push(rawUpdateInfo);
     }
 
     if (viewerInfo && target && viewerInfo.viewer.session === target) {
       // In the case where this update is being created only for the current
       // session, there's no reason to insert a row into the updates table
       continue;
     }
 
     const key = keyForUpdateData(updateData);
     if (key) {
       const conditionKey = `${updateData.userID}|${key}`;
       const currentEarliestTime = earliestTime.get(conditionKey);
       if (!currentEarliestTime || updateData.time < currentEarliestTime) {
         earliestTime.set(conditionKey, updateData.time);
       }
     }
 
     const insertRow = [
       ids[i],
       updateData.userID,
       updateData.type,
       key,
       content,
       updateData.time,
       dontBroadcastSession,
       target,
     ];
     insertRows.push(insertRow);
   }
 
   type DeleteUpdatesConditions = {
     key: string,
     target?: string,
     types?: number[],
     time?: number,
   };
   const usersByConditions: Map<
     string,
     {
       conditions: DeleteUpdatesConditions,
       users: Set<string>,
     },
   > = new Map();
   for (const [conditionKey, keyUpdateDatas] of keyedUpdateDatas) {
     const deleteConditionByTarget: Map<?string, DeleteCondition> = new Map();
     for (const updateData of keyUpdateDatas) {
       const deleteCondition = getDeleteCondition(updateData);
       invariant(
         deleteCondition,
         `updateData of type ${updateData.type} is in keyedUpdateDatas but ` +
           "doesn't have a deleteCondition",
       );
       const { target, types } = deleteCondition;
 
       const existingDeleteCondition = deleteConditionByTarget.get(target);
       if (!existingDeleteCondition) {
         deleteConditionByTarget.set(target, deleteCondition);
         continue;
       }
 
       const existingTypes = existingDeleteCondition.types;
       if (existingTypes === 'all_types') {
         continue;
       } else if (types === 'all_types') {
         deleteConditionByTarget.set(target, deleteCondition);
         continue;
       }
 
       const mergedTypes = new Set([...types, ...existingTypes]);
       deleteConditionByTarget.set(target, {
         ...deleteCondition,
         types: mergedTypes,
       });
     }
 
     for (const deleteCondition of deleteConditionByTarget.values()) {
       const { userID, target, types } = deleteCondition;
       const key = conditionKey.split('|')[1];
       const conditions: DeleteUpdatesConditions = { key };
       if (target) {
         conditions.target = target;
       }
       if (types !== 'all_types') {
         invariant(types.size > 0, 'deleteCondition had empty types set');
         conditions.types = [...types];
       }
       const earliestTimeForCondition = earliestTime.get(conditionKey);
       if (earliestTimeForCondition) {
         conditions.time = earliestTimeForCondition;
       }
 
       const conditionsKey = JSON.stringify(conditions);
       if (!usersByConditions.has(conditionsKey)) {
         usersByConditions.set(conditionsKey, {
           conditions,
           users: new Set(),
         });
       }
       usersByConditions.get(conditionsKey)?.users.add(userID);
     }
   }
 
   const deleteSQLConditions: SQLStatementType[] = [];
   for (const { conditions, users } of usersByConditions.values()) {
     const sqlConditions = [
       SQL`u.user IN (${[...users]})`,
       SQL`u.key = ${conditions.key}`,
     ];
     if (conditions.target) {
       sqlConditions.push(SQL`u.target = ${conditions.target}`);
     }
     if (conditions.types) {
       sqlConditions.push(SQL`u.type IN (${conditions.types})`);
     }
     if (conditions.time) {
       sqlConditions.push(SQL`u.time < ${conditions.time}`);
     }
     deleteSQLConditions.push(mergeAndConditions(sqlConditions));
   }
 
   const promises = {};
 
   if (insertRows.length > 0) {
     const insertQuery = SQL`
       INSERT INTO updates(id, user, type, \`key\`,
         content, time, updater, target)
     `;
     insertQuery.append(SQL`VALUES ${insertRows}`);
     promises.insert = dbQuery(insertQuery);
   }
 
   if (publishInfos.size > 0) {
     promises.redis = redisPublish(publishInfos.values(), dontBroadcastSession);
   }
 
   if (deleteSQLConditions.length > 0) {
     promises.delete = (async () => {
       while (deleteSQLConditions.length > 0) {
         const batch = deleteSQLConditions.splice(0, deleteUpdatesBatchSize);
         await deleteUpdatesByConditions(batch);
       }
     })();
   }
 
   if (viewerRawUpdateInfos.length > 0) {
     invariant(viewerInfo, 'should be set');
     promises.updatesResult = fetchUpdateInfosWithRawUpdateInfos(
       viewerRawUpdateInfos,
       viewerInfo,
     );
   }
 
   const { updatesResult } = await promiseAll(promises);
   if (!updatesResult) {
     return defaultUpdateCreationResult;
   }
   const { updateInfos, userInfos } = updatesResult;
   return { viewerUpdates: updateInfos, userInfos };
 }
 
 export type FetchUpdatesResult = {
   +updateInfos: $ReadOnlyArray<ServerUpdateInfo>,
   +userInfos: UserInfos,
 };
 async function fetchUpdateInfosWithRawUpdateInfos(
   rawUpdateInfos: $ReadOnlyArray<RawUpdateInfo>,
   viewerInfo: ViewerInfo,
 ): Promise<FetchUpdatesResult> {
   const { viewer } = viewerInfo;
 
   const threadIDsNeedingFetch = new Set();
   const entryIDsNeedingFetch = new Set();
   let currentUserNeedsFetch = false;
   const threadIDsNeedingDetailedFetch = new Set(); // entries and messages
   for (const rawUpdateInfo of rawUpdateInfos) {
     if (
       !viewerInfo.threadInfos &&
       (rawUpdateInfo.type === updateTypes.UPDATE_THREAD ||
         rawUpdateInfo.type === updateTypes.JOIN_THREAD)
     ) {
       threadIDsNeedingFetch.add(rawUpdateInfo.threadID);
     }
     if (rawUpdateInfo.type === updateTypes.JOIN_THREAD) {
       threadIDsNeedingDetailedFetch.add(rawUpdateInfo.threadID);
     } else if (rawUpdateInfo.type === updateTypes.UPDATE_ENTRY) {
       entryIDsNeedingFetch.add(rawUpdateInfo.entryID);
     } else if (rawUpdateInfo.type === updateTypes.UPDATE_CURRENT_USER) {
       currentUserNeedsFetch = true;
     }
   }
 
   const promises = {};
 
   if (!viewerInfo.threadInfos && threadIDsNeedingFetch.size > 0) {
     promises.threadResult = fetchThreadInfos(
       viewer,
       SQL`t.id IN (${[...threadIDsNeedingFetch]})`,
     );
   }
 
   let calendarQuery: ?CalendarQuery = viewerInfo.calendarQuery
     ? viewerInfo.calendarQuery
     : null;
   if (!calendarQuery && viewer.hasSessionInfo) {
     // This should only ever happen for "legacy" clients who call in without
     // providing this information. These clients wouldn't know how to deal with
     // the corresponding UpdateInfos anyways, so no reason to be worried.
     calendarQuery = viewer.calendarQuery;
   } else if (!calendarQuery) {
     calendarQuery = defaultCalendarQuery(viewer.platform, viewer.timeZone);
   }
   if (threadIDsNeedingDetailedFetch.size > 0) {
-    const threadSelectionCriteria = { threadCursors: {} };
+    const messageSelectionCriteria = { threadCursors: {} };
     for (const threadID of threadIDsNeedingDetailedFetch) {
-      threadSelectionCriteria.threadCursors[threadID] = false;
+      messageSelectionCriteria.threadCursors[threadID] = false;
     }
     promises.messageInfosResult = fetchMessageInfos(
       viewer,
-      threadSelectionCriteria,
+      messageSelectionCriteria,
       defaultNumberPerThread,
     );
     const threadCalendarQuery = {
       ...calendarQuery,
       filters: [
         ...nonThreadCalendarFilters(calendarQuery.filters),
         { type: 'threads', threadIDs: [...threadIDsNeedingDetailedFetch] },
       ],
     };
     promises.calendarResult = fetchEntryInfos(viewer, [threadCalendarQuery]);
   }
 
   if (entryIDsNeedingFetch.size > 0) {
     promises.entryInfosResult = fetchEntryInfosByID(viewer, [
       ...entryIDsNeedingFetch,
     ]);
   }
 
   if (currentUserNeedsFetch) {
     promises.currentUserInfoResult = (async () => {
       const currentUserInfo = await fetchCurrentUserInfo(viewer);
       invariant(currentUserInfo.anonymous === undefined, 'should be logged in');
       return currentUserInfo;
     })();
   }
 
   const {
     threadResult,
     messageInfosResult,
     calendarResult,
     entryInfosResult,
     currentUserInfoResult,
   } = await promiseAll(promises);
 
   let threadInfosResult;
   if (viewerInfo.threadInfos) {
     const { threadInfos } = viewerInfo;
     threadInfosResult = { threadInfos };
   } else if (threadResult) {
     threadInfosResult = threadResult;
   } else {
     threadInfosResult = { threadInfos: {} };
   }
 
   return await updateInfosFromRawUpdateInfos(viewer, rawUpdateInfos, {
     threadInfosResult,
     messageInfosResult,
     calendarResult,
     entryInfosResult,
     currentUserInfoResult,
   });
 }
 
 export type UpdateInfosRawData = {
   threadInfosResult: FetchThreadInfosResult,
   messageInfosResult: ?FetchMessageInfosResult,
   calendarResult: ?FetchEntryInfosBase,
   entryInfosResult: ?$ReadOnlyArray<RawEntryInfo>,
   currentUserInfoResult: ?OldLoggedInUserInfo | LoggedInUserInfo,
 };
 async function updateInfosFromRawUpdateInfos(
   viewer: Viewer,
   rawUpdateInfos: $ReadOnlyArray<RawUpdateInfo>,
   rawData: UpdateInfosRawData,
 ): Promise<FetchUpdatesResult> {
   const {
     threadInfosResult,
     messageInfosResult,
     calendarResult,
     entryInfosResult,
     currentUserInfoResult,
   } = rawData;
   const updateInfos = [];
   const userIDsToFetch = new Set();
   for (const rawUpdateInfo of rawUpdateInfos) {
     if (rawUpdateInfo.type === updateTypes.DELETE_ACCOUNT) {
       updateInfos.push({
         type: updateTypes.DELETE_ACCOUNT,
         id: rawUpdateInfo.id,
         time: rawUpdateInfo.time,
         deletedUserID: rawUpdateInfo.deletedUserID,
       });
     } else if (rawUpdateInfo.type === updateTypes.UPDATE_THREAD) {
       const threadInfo = threadInfosResult.threadInfos[rawUpdateInfo.threadID];
       if (!threadInfo) {
         console.warn(
           "failed to hydrate updateTypes.UPDATE_THREAD because we couldn't " +
             `fetch RawThreadInfo for ${rawUpdateInfo.threadID}`,
         );
         continue;
       }
       updateInfos.push({
         type: updateTypes.UPDATE_THREAD,
         id: rawUpdateInfo.id,
         time: rawUpdateInfo.time,
         threadInfo,
       });
     } else if (rawUpdateInfo.type === updateTypes.UPDATE_THREAD_READ_STATUS) {
       updateInfos.push({
         type: updateTypes.UPDATE_THREAD_READ_STATUS,
         id: rawUpdateInfo.id,
         time: rawUpdateInfo.time,
         threadID: rawUpdateInfo.threadID,
         unread: rawUpdateInfo.unread,
       });
     } else if (rawUpdateInfo.type === updateTypes.DELETE_THREAD) {
       updateInfos.push({
         type: updateTypes.DELETE_THREAD,
         id: rawUpdateInfo.id,
         time: rawUpdateInfo.time,
         threadID: rawUpdateInfo.threadID,
       });
     } else if (rawUpdateInfo.type === updateTypes.JOIN_THREAD) {
       const threadInfo = threadInfosResult.threadInfos[rawUpdateInfo.threadID];
       if (!threadInfo) {
         console.warn(
           "failed to hydrate updateTypes.JOIN_THREAD because we couldn't " +
             `fetch RawThreadInfo for ${rawUpdateInfo.threadID}`,
         );
         continue;
       }
       const rawEntryInfos = [];
       invariant(calendarResult, 'should be set');
       for (const entryInfo of calendarResult.rawEntryInfos) {
         if (entryInfo.threadID === rawUpdateInfo.threadID) {
           rawEntryInfos.push(entryInfo);
         }
       }
       const rawMessageInfos = [];
       invariant(messageInfosResult, 'should be set');
       for (const messageInfo of messageInfosResult.rawMessageInfos) {
         if (messageInfo.threadID === rawUpdateInfo.threadID) {
           rawMessageInfos.push(messageInfo);
         }
       }
       updateInfos.push({
         type: updateTypes.JOIN_THREAD,
         id: rawUpdateInfo.id,
         time: rawUpdateInfo.time,
         threadInfo,
         rawMessageInfos,
         truncationStatus:
           messageInfosResult.truncationStatuses[rawUpdateInfo.threadID],
         rawEntryInfos,
       });
     } else if (rawUpdateInfo.type === updateTypes.BAD_DEVICE_TOKEN) {
       updateInfos.push({
         type: updateTypes.BAD_DEVICE_TOKEN,
         id: rawUpdateInfo.id,
         time: rawUpdateInfo.time,
         deviceToken: rawUpdateInfo.deviceToken,
       });
     } else if (rawUpdateInfo.type === updateTypes.UPDATE_ENTRY) {
       invariant(entryInfosResult, 'should be set');
       const entryInfo = entryInfosResult.find(
         candidate => candidate.id === rawUpdateInfo.entryID,
       );
       if (!entryInfo) {
         console.warn(
           "failed to hydrate updateTypes.UPDATE_ENTRY because we couldn't " +
             `fetch RawEntryInfo for ${rawUpdateInfo.entryID}`,
         );
         continue;
       }
       updateInfos.push({
         type: updateTypes.UPDATE_ENTRY,
         id: rawUpdateInfo.id,
         time: rawUpdateInfo.time,
         entryInfo,
       });
     } else if (rawUpdateInfo.type === updateTypes.UPDATE_CURRENT_USER) {
       invariant(currentUserInfoResult, 'should be set');
       updateInfos.push({
         type: updateTypes.UPDATE_CURRENT_USER,
         id: rawUpdateInfo.id,
         time: rawUpdateInfo.time,
         currentUserInfo: currentUserInfoResult,
       });
     } else if (rawUpdateInfo.type === updateTypes.UPDATE_USER) {
       updateInfos.push({
         type: updateTypes.UPDATE_USER,
         id: rawUpdateInfo.id,
         time: rawUpdateInfo.time,
         updatedUserID: rawUpdateInfo.updatedUserID,
       });
       userIDsToFetch.add(rawUpdateInfo.updatedUserID);
     } else {
       invariant(false, `unrecognized updateType ${rawUpdateInfo.type}`);
     }
   }
 
   let userInfos = {};
   if (userIDsToFetch.size > 0) {
     userInfos = await fetchKnownUserInfos(viewer, [...userIDsToFetch]);
   }
 
   updateInfos.sort(sortFunction);
 
   // Now we'll attempt to merge UpdateInfos so that we only have one per key
   const updateForKey: Map<string, ServerUpdateInfo> = new Map();
   const mergedUpdates: ServerUpdateInfo[] = [];
   for (const updateInfo of updateInfos) {
     const key = keyForUpdateInfo(updateInfo);
     if (!key) {
       mergedUpdates.push(updateInfo);
       continue;
     } else if (
       updateInfo.type === updateTypes.DELETE_THREAD ||
       updateInfo.type === updateTypes.JOIN_THREAD ||
       updateInfo.type === updateTypes.DELETE_ACCOUNT
     ) {
       updateForKey.set(key, updateInfo);
       continue;
     }
     const currentUpdateInfo = updateForKey.get(key);
     if (!currentUpdateInfo) {
       updateForKey.set(key, updateInfo);
     } else if (
       updateInfo.type === updateTypes.UPDATE_THREAD &&
       currentUpdateInfo.type === updateTypes.UPDATE_THREAD_READ_STATUS
     ) {
       // UPDATE_THREAD trumps UPDATE_THREAD_READ_STATUS
       // Note that we keep the oldest UPDATE_THREAD
       updateForKey.set(key, updateInfo);
     } else if (
       updateInfo.type === updateTypes.UPDATE_THREAD_READ_STATUS &&
       currentUpdateInfo.type === updateTypes.UPDATE_THREAD_READ_STATUS
     ) {
       // If we only have UPDATE_THREAD_READ_STATUS, keep the most recent
       updateForKey.set(key, updateInfo);
     } else if (updateInfo.type === updateTypes.UPDATE_ENTRY) {
       updateForKey.set(key, updateInfo);
     } else if (updateInfo.type === updateTypes.UPDATE_CURRENT_USER) {
       updateForKey.set(key, updateInfo);
     }
   }
   for (const [, updateInfo] of updateForKey) {
     mergedUpdates.push(updateInfo);
   }
   mergedUpdates.sort(sortFunction);
 
   return { updateInfos: mergedUpdates, userInfos };
 }
 
 type PublishInfo = {
   updateTarget: UpdateTarget,
   rawUpdateInfos: RawUpdateInfo[],
 };
 async function redisPublish(
   publishInfos: Iterator<PublishInfo>,
   dontBroadcastSession: ?string,
 ): Promise<void> {
   for (const publishInfo of publishInfos) {
     const { updateTarget, rawUpdateInfos } = publishInfo;
     const redisMessage: NewUpdatesRedisMessage = {
       type: redisMessageTypes.NEW_UPDATES,
       updates: rawUpdateInfos,
     };
     if (!updateTarget.sessionID && dontBroadcastSession) {
       redisMessage.ignoreSession = dontBroadcastSession;
     }
     publisher.sendMessage(updateTarget, redisMessage);
   }
 }
 
 function getTargetFromUpdateData(updateData: UpdateData): ?string {
   if (updateData.targetSession) {
     return updateData.targetSession;
   } else if (updateData.targetCookie) {
     return updateData.targetCookie;
   } else {
     return null;
   }
 }
 
 function getDeleteCondition(updateData: UpdateData): ?DeleteCondition {
   let types;
   if (updateData.type === updateTypes.DELETE_ACCOUNT) {
     types = new Set([updateTypes.DELETE_ACCOUNT, updateTypes.UPDATE_USER]);
   } else if (updateData.type === updateTypes.UPDATE_THREAD) {
     types = new Set([
       updateTypes.UPDATE_THREAD,
       updateTypes.UPDATE_THREAD_READ_STATUS,
     ]);
   } else if (updateData.type === updateTypes.UPDATE_THREAD_READ_STATUS) {
     types = new Set([updateTypes.UPDATE_THREAD_READ_STATUS]);
   } else if (
     updateData.type === updateTypes.DELETE_THREAD ||
     updateData.type === updateTypes.JOIN_THREAD
   ) {
     types = 'all_types';
   } else if (updateData.type === updateTypes.UPDATE_ENTRY) {
     types = 'all_types';
   } else if (updateData.type === updateTypes.UPDATE_CURRENT_USER) {
     types = new Set([updateTypes.UPDATE_CURRENT_USER]);
   } else if (updateData.type === updateTypes.UPDATE_USER) {
     types = new Set([updateTypes.UPDATE_USER]);
   } else {
     return null;
   }
 
   const target = getTargetFromUpdateData(updateData);
   const { userID } = updateData;
   return { userID, target, types };
 }
 
 function filterOnDeleteCondition(
   updateData: UpdateData,
   deleteCondition: DeleteCondition,
 ): boolean {
   invariant(
     updateData.userID === deleteCondition.userID,
     `updateData of type ${updateData.type} being compared to wrong userID`,
   );
   if (deleteCondition.target) {
     const target = getTargetFromUpdateData(updateData);
     if (target !== deleteCondition.target) {
       return true;
     }
   }
   if (deleteCondition.types === 'all_types') {
     return false;
   }
   return !deleteCondition.types.has(updateData.type);
 }
 
 export { createUpdates, fetchUpdateInfosWithRawUpdateInfos };
diff --git a/server/src/fetchers/message-fetchers.js b/server/src/fetchers/message-fetchers.js
index 579272cf3..fb9fad0af 100644
--- a/server/src/fetchers/message-fetchers.js
+++ b/server/src/fetchers/message-fetchers.js
@@ -1,611 +1,613 @@
 // @flow
 
 import invariant from 'invariant';
 
 import {
   sortMessageInfoList,
   shimUnsupportedRawMessageInfos,
 } from 'lib/shared/message-utils';
 import { messageSpecs } from 'lib/shared/messages/message-specs';
 import { notifCollapseKeyForRawMessageInfo } from 'lib/shared/notif-utils';
 import {
   type RawMessageInfo,
   type RawComposableMessageInfo,
   type RawRobotextMessageInfo,
   messageTypes,
   type MessageType,
   assertMessageType,
-  type ThreadSelectionCriteria,
+  type MessageSelectionCriteria,
   type MessageTruncationStatus,
   messageTruncationStatus,
   type FetchMessageInfosResult,
 } from 'lib/types/message-types';
 import { threadPermissions } from 'lib/types/thread-types';
 import { ServerError } from 'lib/utils/errors';
 
 import { dbQuery, SQL, mergeOrConditions } from '../database/database';
 import type { PushInfo } from '../push/send';
 import type { Viewer } from '../session/viewer';
 import { creationString, localIDFromCreationString } from '../utils/idempotent';
 import { mediaFromRow } from './upload-fetchers';
 
 export type CollapsableNotifInfo = {
   collapseKey: ?string,
   existingMessageInfos: RawMessageInfo[],
   newMessageInfos: RawMessageInfo[],
 };
 export type FetchCollapsableNotifsResult = {
   [userID: string]: CollapsableNotifInfo[],
 };
 
 const visibleExtractString = `$.${threadPermissions.VISIBLE}.value`;
 
 // This function doesn't filter RawMessageInfos based on what messageTypes the
 // client supports, since each user can have multiple clients. The caller must
 // handle this filtering.
 async function fetchCollapsableNotifs(
   pushInfo: PushInfo,
 ): Promise<FetchCollapsableNotifsResult> {
   // First, we need to fetch any notifications that should be collapsed
   const usersToCollapseKeysToInfo = {};
   const usersToCollapsableNotifInfo = {};
   for (const userID in pushInfo) {
     usersToCollapseKeysToInfo[userID] = {};
     usersToCollapsableNotifInfo[userID] = [];
     for (const rawMessageInfo of pushInfo[userID].messageInfos) {
       const collapseKey = notifCollapseKeyForRawMessageInfo(rawMessageInfo);
       if (!collapseKey) {
         const collapsableNotifInfo = {
           collapseKey,
           existingMessageInfos: [],
           newMessageInfos: [rawMessageInfo],
         };
         usersToCollapsableNotifInfo[userID].push(collapsableNotifInfo);
         continue;
       }
       if (!usersToCollapseKeysToInfo[userID][collapseKey]) {
         usersToCollapseKeysToInfo[userID][collapseKey] = {
           collapseKey,
           existingMessageInfos: [],
           newMessageInfos: [],
         };
       }
       usersToCollapseKeysToInfo[userID][collapseKey].newMessageInfos.push(
         rawMessageInfo,
       );
     }
   }
 
   const sqlTuples = [];
   for (const userID in usersToCollapseKeysToInfo) {
     const collapseKeysToInfo = usersToCollapseKeysToInfo[userID];
     for (const collapseKey in collapseKeysToInfo) {
       sqlTuples.push(
         SQL`(n.user = ${userID} AND n.collapse_key = ${collapseKey})`,
       );
     }
   }
 
   if (sqlTuples.length === 0) {
     return usersToCollapsableNotifInfo;
   }
 
   const collapseQuery = SQL`
     SELECT m.id, m.thread AS threadID, m.content, m.time, m.type,
       m.user AS creatorID, stm.permissions AS subthread_permissions, n.user,
       n.collapse_key, up.id AS uploadID, up.type AS uploadType,
       up.secret AS uploadSecret, up.extra AS uploadExtra
     FROM notifications n
     LEFT JOIN messages m ON m.id = n.message
     LEFT JOIN uploads up
       ON m.type IN (${[messageTypes.IMAGES, messageTypes.MULTIMEDIA]})
         AND JSON_CONTAINS(m.content, CAST(up.id as JSON), '$')
     LEFT JOIN memberships mm ON mm.thread = m.thread AND mm.user = n.user
     LEFT JOIN memberships stm
       ON m.type = ${messageTypes.CREATE_SUB_THREAD}
         AND stm.thread = m.content AND stm.user = n.user
     WHERE n.rescinded = 0 AND
       JSON_EXTRACT(mm.permissions, ${visibleExtractString}) IS TRUE AND
   `;
   collapseQuery.append(mergeOrConditions(sqlTuples));
   collapseQuery.append(SQL`ORDER BY m.time DESC`);
   const [collapseResult] = await dbQuery(collapseQuery);
 
   const rowsByUser = new Map();
   for (const row of collapseResult) {
     const user = row.user.toString();
     const currentRowsForUser = rowsByUser.get(user);
     if (currentRowsForUser) {
       currentRowsForUser.push(row);
     } else {
       rowsByUser.set(user, [row]);
     }
   }
 
   const derivedMessages = await fetchDerivedMessages(collapseResult);
   for (const userRows of rowsByUser.values()) {
     const messages = parseMessageSQLResult(userRows, derivedMessages);
     for (const message of messages) {
       const { rawMessageInfo, rows } = message;
       const [row] = rows;
       const info = usersToCollapseKeysToInfo[row.user][row.collapse_key];
       info.existingMessageInfos.push(rawMessageInfo);
     }
   }
 
   for (const userID in usersToCollapseKeysToInfo) {
     const collapseKeysToInfo = usersToCollapseKeysToInfo[userID];
     for (const collapseKey in collapseKeysToInfo) {
       const info = collapseKeysToInfo[collapseKey];
       usersToCollapsableNotifInfo[userID].push({
         collapseKey: info.collapseKey,
         existingMessageInfos: sortMessageInfoList(info.existingMessageInfos),
         newMessageInfos: sortMessageInfoList(info.newMessageInfos),
       });
     }
   }
 
   return usersToCollapsableNotifInfo;
 }
 
 type MessageSQLResult = $ReadOnlyArray<{
   rawMessageInfo: RawMessageInfo,
   rows: $ReadOnlyArray<Object>,
 }>;
 function parseMessageSQLResult(
   rows: $ReadOnlyArray<Object>,
   derivedMessages: $ReadOnlyMap<
     string,
     RawComposableMessageInfo | RawRobotextMessageInfo,
   >,
   viewer?: Viewer,
 ): MessageSQLResult {
   const rowsByID = new Map();
   for (const row of rows) {
     const id = row.id.toString();
     const currentRowsForID = rowsByID.get(id);
     if (currentRowsForID) {
       currentRowsForID.push(row);
     } else {
       rowsByID.set(id, [row]);
     }
   }
 
   const messages = [];
   for (const messageRows of rowsByID.values()) {
     const rawMessageInfo = rawMessageInfoFromRows(
       messageRows,
       viewer,
       derivedMessages,
     );
     if (rawMessageInfo) {
       messages.push({ rawMessageInfo, rows: messageRows });
     }
   }
 
   return messages;
 }
 
 function assertSingleRow(rows: $ReadOnlyArray<Object>): Object {
   if (rows.length === 0) {
     throw new Error('expected single row, but none present!');
   } else if (rows.length !== 1) {
     const messageIDs = rows.map(row => row.id.toString());
     console.warn(
       `expected single row, but there are multiple! ${messageIDs.join(', ')}`,
     );
   }
   return rows[0];
 }
 
 function mostRecentRowType(rows: $ReadOnlyArray<Object>): MessageType {
   if (rows.length === 0) {
     throw new Error('expected row, but none present!');
   }
   return assertMessageType(rows[0].type);
 }
 
 function rawMessageInfoFromRows(
   rows: $ReadOnlyArray<Object>,
   viewer?: Viewer,
   derivedMessages: $ReadOnlyMap<
     string,
     RawComposableMessageInfo | RawRobotextMessageInfo,
   >,
 ): ?RawMessageInfo {
   const type = mostRecentRowType(rows);
   const messageSpec = messageSpecs[type];
 
   if (type === messageTypes.IMAGES || type === messageTypes.MULTIMEDIA) {
     const media = rows.filter(row => row.uploadID).map(mediaFromRow);
     const [row] = rows;
     const localID = localIDFromCreationString(viewer, row.creation);
     invariant(
       messageSpec.rawMessageInfoFromServerDBRow,
       `multimedia message spec should have rawMessageInfoFromServerDBRow`,
     );
     return messageSpec.rawMessageInfoFromServerDBRow(row, {
       media,
       derivedMessages,
       localID,
     });
   }
 
   const row = assertSingleRow(rows);
   const localID = localIDFromCreationString(viewer, row.creation);
   invariant(
     messageSpec.rawMessageInfoFromServerDBRow,
     `message spec ${type} should have rawMessageInfoFromServerDBRow`,
   );
   return messageSpec.rawMessageInfoFromServerDBRow(row, {
     derivedMessages,
     localID,
   });
 }
 
 async function fetchMessageInfos(
   viewer: Viewer,
-  criteria: ThreadSelectionCriteria,
+  criteria: MessageSelectionCriteria,
   numberPerThread: number,
 ): Promise<FetchMessageInfosResult> {
-  const threadSelectionClause = threadSelectionCriteriaToSQLClause(criteria);
+  const selectionClause = messageSelectionCriteriaToSQLClause(criteria);
   const truncationStatuses = {};
 
   const viewerID = viewer.id;
   const query = SQL`
     SELECT * FROM (
       SELECT x.id, x.content, x.time, x.type, x.user AS creatorID,
         x.creation, x.subthread_permissions, x.uploadID, x.uploadType,
         x.uploadSecret, x.uploadExtra,
         @num := if(
           @thread = x.thread,
           if(@message = x.id, @num, @num + 1),
           1
         ) AS number,
         @message := x.id AS messageID,
         @thread := x.thread AS threadID
       FROM (SELECT @num := 0, @thread := '', @message := '') init
       JOIN (
         SELECT m.id, m.thread, m.user, m.content, m.time, m.type,
           m.creation, stm.permissions AS subthread_permissions,
           up.id AS uploadID, up.type AS uploadType, up.secret AS uploadSecret,
           up.extra AS uploadExtra
         FROM messages m
         LEFT JOIN uploads up
           ON m.type IN (${[messageTypes.IMAGES, messageTypes.MULTIMEDIA]})
             AND JSON_CONTAINS(m.content, CAST(up.id as JSON), '$')
         LEFT JOIN memberships mm
           ON mm.thread = m.thread AND mm.user = ${viewerID}
         LEFT JOIN memberships stm ON m.type = ${messageTypes.CREATE_SUB_THREAD}
           AND stm.thread = m.content AND stm.user = ${viewerID}
         WHERE JSON_EXTRACT(mm.permissions, ${visibleExtractString}) IS TRUE AND
   `;
-  query.append(threadSelectionClause);
+  query.append(selectionClause);
   query.append(SQL`
         ORDER BY m.thread, m.time DESC
       ) x
     ) y
     WHERE y.number <= ${numberPerThread}
   `);
   const [result] = await dbQuery(query);
   const derivedMessages = await fetchDerivedMessages(result, viewer);
   const messages = parseMessageSQLResult(result, derivedMessages, viewer);
 
   const rawMessageInfos = [];
   const threadToMessageCount = new Map();
   for (const message of messages) {
     const { rawMessageInfo } = message;
     rawMessageInfos.push(rawMessageInfo);
     const { threadID } = rawMessageInfo;
     const currentCountValue = threadToMessageCount.get(threadID);
     const currentCount = currentCountValue ? currentCountValue : 0;
     threadToMessageCount.set(threadID, currentCount + 1);
   }
 
   for (const [threadID, messageCount] of threadToMessageCount) {
     // If there are fewer messages returned than the max for a given thread,
     // then our result set includes all messages in the query range for that
     // thread
     truncationStatuses[threadID] =
       messageCount < numberPerThread
         ? messageTruncationStatus.EXHAUSTIVE
         : messageTruncationStatus.TRUNCATED;
   }
 
   for (const rawMessageInfo of rawMessageInfos) {
     if (messageSpecs[rawMessageInfo.type].startsThread) {
       truncationStatuses[rawMessageInfo.threadID] =
         messageTruncationStatus.EXHAUSTIVE;
     }
   }
 
   for (const threadID in criteria.threadCursors) {
     const truncationStatus = truncationStatuses[threadID];
     if (truncationStatus === null || truncationStatus === undefined) {
       // If nothing was returned for a thread that was explicitly queried for,
       // then our result set includes all messages in the query range for that
       // thread
       truncationStatuses[threadID] = messageTruncationStatus.EXHAUSTIVE;
     } else if (truncationStatus === messageTruncationStatus.TRUNCATED) {
       // If a cursor was specified for a given thread, then the result is
       // guaranteed to be contiguous with what the client has, and as such the
       // result should never be TRUNCATED
       truncationStatuses[threadID] = messageTruncationStatus.UNCHANGED;
     }
   }
 
   const shimmedRawMessageInfos = shimUnsupportedRawMessageInfos(
     rawMessageInfos,
     viewer.platformDetails,
   );
 
   return {
     rawMessageInfos: shimmedRawMessageInfos,
     truncationStatuses,
   };
 }
 
-function threadSelectionCriteriaToSQLClause(criteria: ThreadSelectionCriteria) {
+function messageSelectionCriteriaToSQLClause(
+  criteria: MessageSelectionCriteria,
+) {
   const conditions = [];
   if (criteria.joinedThreads === true) {
     conditions.push(SQL`mm.role > 0`);
   }
   if (criteria.threadCursors) {
     for (const threadID in criteria.threadCursors) {
       const cursor = criteria.threadCursors[threadID];
       if (cursor) {
         conditions.push(SQL`(m.thread = ${threadID} AND m.id < ${cursor})`);
       } else {
         conditions.push(SQL`m.thread = ${threadID}`);
       }
     }
   }
   if (conditions.length === 0) {
     throw new ServerError('internal_error');
   }
   return mergeOrConditions(conditions);
 }
 
-function threadSelectionCriteriaToInitialTruncationStatuses(
-  criteria: ThreadSelectionCriteria,
+function messageSelectionCriteriaToInitialTruncationStatuses(
+  criteria: MessageSelectionCriteria,
   defaultTruncationStatus: MessageTruncationStatus,
 ) {
   const truncationStatuses = {};
   if (criteria.threadCursors) {
     for (const threadID in criteria.threadCursors) {
       truncationStatuses[threadID] = defaultTruncationStatus;
     }
   }
   return truncationStatuses;
 }
 
 async function fetchMessageInfosSince(
   viewer: Viewer,
-  criteria: ThreadSelectionCriteria,
+  criteria: MessageSelectionCriteria,
   currentAsOf: number,
   maxNumberPerThread: number,
 ): Promise<FetchMessageInfosResult> {
-  const threadSelectionClause = threadSelectionCriteriaToSQLClause(criteria);
-  const truncationStatuses = threadSelectionCriteriaToInitialTruncationStatuses(
+  const selectionClause = messageSelectionCriteriaToSQLClause(criteria);
+  const truncationStatuses = messageSelectionCriteriaToInitialTruncationStatuses(
     criteria,
     messageTruncationStatus.UNCHANGED,
   );
 
   const viewerID = viewer.id;
   const query = SQL`
     SELECT m.id, m.thread AS threadID, m.content, m.time, m.type,
       m.creation, m.user AS creatorID, stm.permissions AS subthread_permissions,
       up.id AS uploadID, up.type AS uploadType, up.secret AS uploadSecret,
       up.extra AS uploadExtra
     FROM messages m
     LEFT JOIN uploads up
       ON m.type IN (${[messageTypes.IMAGES, messageTypes.MULTIMEDIA]})
         AND JSON_CONTAINS(m.content, CAST(up.id as JSON), '$')
     LEFT JOIN memberships mm ON mm.thread = m.thread AND mm.user = ${viewerID}
     LEFT JOIN memberships stm ON m.type = ${messageTypes.CREATE_SUB_THREAD}
       AND stm.thread = m.content AND stm.user = ${viewerID}
     WHERE m.time > ${currentAsOf} AND
       JSON_EXTRACT(mm.permissions, ${visibleExtractString}) IS TRUE AND
   `;
-  query.append(threadSelectionClause);
+  query.append(selectionClause);
   query.append(SQL`
     ORDER BY m.thread, m.time DESC
   `);
   const [result] = await dbQuery(query);
   const derivedMessages = await fetchDerivedMessages(result, viewer);
   const messages = parseMessageSQLResult(result, derivedMessages, viewer);
 
   const rawMessageInfos = [];
   let currentThreadID = null;
   let numMessagesForCurrentThreadID = 0;
   for (const message of messages) {
     const { rawMessageInfo } = message;
     const { threadID } = rawMessageInfo;
     if (threadID !== currentThreadID) {
       currentThreadID = threadID;
       numMessagesForCurrentThreadID = 1;
       truncationStatuses[threadID] = messageTruncationStatus.UNCHANGED;
     } else {
       numMessagesForCurrentThreadID++;
     }
     if (numMessagesForCurrentThreadID <= maxNumberPerThread) {
       if (messageSpecs[rawMessageInfo.type].startsThread) {
         truncationStatuses[threadID] = messageTruncationStatus.EXHAUSTIVE;
       }
       rawMessageInfos.push(rawMessageInfo);
     } else if (numMessagesForCurrentThreadID === maxNumberPerThread + 1) {
       truncationStatuses[threadID] = messageTruncationStatus.TRUNCATED;
     }
   }
 
   const shimmedRawMessageInfos = shimUnsupportedRawMessageInfos(
     rawMessageInfos,
     viewer.platformDetails,
   );
 
   return {
     rawMessageInfos: shimmedRawMessageInfos,
     truncationStatuses,
   };
 }
 
 function getMessageFetchResultFromRedisMessages(
   viewer: Viewer,
   rawMessageInfos: $ReadOnlyArray<RawMessageInfo>,
 ): FetchMessageInfosResult {
   const truncationStatuses = {};
   for (const rawMessageInfo of rawMessageInfos) {
     truncationStatuses[rawMessageInfo.threadID] =
       messageTruncationStatus.UNCHANGED;
   }
   const shimmedRawMessageInfos = shimUnsupportedRawMessageInfos(
     rawMessageInfos,
     viewer.platformDetails,
   );
   return {
     rawMessageInfos: shimmedRawMessageInfos,
     truncationStatuses,
   };
 }
 
 async function fetchMessageInfoForLocalID(
   viewer: Viewer,
   localID: ?string,
 ): Promise<?RawMessageInfo> {
   if (!localID || !viewer.hasSessionInfo) {
     return null;
   }
   const creation = creationString(viewer, localID);
   const viewerID = viewer.id;
   const query = SQL`
     SELECT m.id, m.thread AS threadID, m.content, m.time, m.type, m.creation,
       m.user AS creatorID, stm.permissions AS subthread_permissions,
       up.id AS uploadID, up.type AS uploadType, up.secret AS uploadSecret,
       up.extra AS uploadExtra
     FROM messages m
     LEFT JOIN uploads up
       ON m.type IN (${[messageTypes.IMAGES, messageTypes.MULTIMEDIA]})
         AND JSON_CONTAINS(m.content, CAST(up.id as JSON), '$')
     LEFT JOIN memberships mm ON mm.thread = m.thread AND mm.user = ${viewerID}
     LEFT JOIN memberships stm ON m.type = ${messageTypes.CREATE_SUB_THREAD}
       AND stm.thread = m.content AND stm.user = ${viewerID}
     WHERE m.user = ${viewerID} AND m.creation = ${creation} AND
       JSON_EXTRACT(mm.permissions, ${visibleExtractString}) IS TRUE
   `;
 
   const [result] = await dbQuery(query);
   if (result.length === 0) {
     return null;
   }
   const derivedMessages = await fetchDerivedMessages(result, viewer);
   return rawMessageInfoFromRows(result, viewer, derivedMessages);
 }
 
 const entryIDExtractString = '$.entryID';
 async function fetchMessageInfoForEntryAction(
   viewer: Viewer,
   messageType: MessageType,
   entryID: string,
   threadID: string,
 ): Promise<?RawMessageInfo> {
   const viewerID = viewer.id;
   const query = SQL`
     SELECT m.id, m.thread AS threadID, m.content, m.time, m.type, m.creation,
       m.user AS creatorID, up.id AS uploadID, up.type AS uploadType,
       up.secret AS uploadSecret, up.extra AS uploadExtra
     FROM messages m
     LEFT JOIN uploads up
       ON m.type IN (${[messageTypes.IMAGES, messageTypes.MULTIMEDIA]})
         AND JSON_CONTAINS(m.content, CAST(up.id as JSON), '$')
     LEFT JOIN memberships mm ON mm.thread = m.thread AND mm.user = ${viewerID}
     WHERE m.user = ${viewerID} AND m.thread = ${threadID} AND
       m.type = ${messageType} AND
       JSON_EXTRACT(m.content, ${entryIDExtractString}) = ${entryID} AND
       JSON_EXTRACT(mm.permissions, ${visibleExtractString}) IS TRUE
   `;
 
   const [result] = await dbQuery(query);
   if (result.length === 0) {
     return null;
   }
   const derivedMessages = await fetchDerivedMessages(result, viewer);
   return rawMessageInfoFromRows(result, viewer, derivedMessages);
 }
 
 async function fetchMessageRowsByIDs(messageIDs: $ReadOnlyArray<string>) {
   const query = SQL`
     SELECT m.id, m.thread AS threadID, m.content, m.time, m.type, m.creation, 
       m.user AS creatorID, stm.permissions AS subthread_permissions,
       up.id AS uploadID, up.type AS uploadType, up.secret AS uploadSecret, 
       up.extra AS uploadExtra
     FROM messages m
     LEFT JOIN uploads up
       ON m.type IN (${[messageTypes.IMAGES, messageTypes.MULTIMEDIA]})
         AND JSON_CONTAINS(m.content, CAST(up.id as JSON), '$')
     LEFT JOIN memberships stm ON m.type = ${messageTypes.CREATE_SUB_THREAD}
       AND stm.thread = m.content AND stm.user = m.user
     WHERE m.id IN (${messageIDs})
   `;
   const [result] = await dbQuery(query);
   return result;
 }
 
 async function fetchDerivedMessages(
   rows: $ReadOnlyArray<Object>,
   viewer?: Viewer,
 ): Promise<
   $ReadOnlyMap<string, RawComposableMessageInfo | RawRobotextMessageInfo>,
 > {
   const requiredIDs = new Set<string>();
   for (const row of rows) {
     if (row.type === messageTypes.SIDEBAR_SOURCE) {
       const content = JSON.parse(row.content);
       requiredIDs.add(content.sourceMessageID);
     }
   }
 
   const messagesByID = new Map<
     string,
     RawComposableMessageInfo | RawRobotextMessageInfo,
   >();
   if (requiredIDs.size === 0) {
     return messagesByID;
   }
 
   const result = await fetchMessageRowsByIDs([...requiredIDs]);
   const messages = parseMessageSQLResult(result, new Map(), viewer);
 
   for (const message of messages) {
     const { rawMessageInfo } = message;
     if (rawMessageInfo.id) {
       invariant(
         rawMessageInfo.type !== messageTypes.SIDEBAR_SOURCE,
         'SIDEBAR_SOURCE should not point to a SIDEBAR_SOURCE',
       );
       messagesByID.set(rawMessageInfo.id, rawMessageInfo);
     }
   }
   return messagesByID;
 }
 
 async function fetchMessageInfoByID(
   viewer?: Viewer,
   messageID: string,
 ): Promise<?RawMessageInfo> {
   const result = await fetchMessageRowsByIDs([messageID]);
   if (result.length === 0) {
     return null;
   }
   const derivedMessages = await fetchDerivedMessages(result, viewer);
   return rawMessageInfoFromRows(result, viewer, derivedMessages);
 }
 
 export {
   fetchCollapsableNotifs,
   fetchMessageInfos,
   fetchMessageInfosSince,
   getMessageFetchResultFromRedisMessages,
   fetchMessageInfoForLocalID,
   fetchMessageInfoForEntryAction,
   fetchMessageInfoByID,
 };
diff --git a/server/src/responders/user-responders.js b/server/src/responders/user-responders.js
index 1f3e0049e..c7daca773 100644
--- a/server/src/responders/user-responders.js
+++ b/server/src/responders/user-responders.js
@@ -1,354 +1,354 @@
 // @flow
 
 import invariant from 'invariant';
 import t from 'tcomb';
 import bcrypt from 'twin-bcrypt';
 
 import type {
   ResetPasswordRequest,
   LogOutResponse,
   DeleteAccountRequest,
   RegisterResponse,
   RegisterRequest,
   LogInResponse,
   LogInRequest,
   UpdatePasswordRequest,
   AccessRequest,
   UpdateUserSettingsRequest,
 } from 'lib/types/account-types';
 import {
   userSettingsTypes,
   notificationTypeValues,
 } from 'lib/types/account-types';
 import { defaultNumberPerThread } from 'lib/types/message-types';
 import type {
   SubscriptionUpdateRequest,
   SubscriptionUpdateResponse,
 } from 'lib/types/subscription-types';
 import type { PasswordUpdate } from 'lib/types/user-types';
 import { ServerError } from 'lib/utils/errors';
 import { values } from 'lib/utils/objects';
 import { promiseAll } from 'lib/utils/promises';
 import {
   tShape,
   tPlatformDetails,
   tDeviceType,
   tPassword,
   tEmail,
   tOldValidUsername,
 } from 'lib/utils/validation-utils';
 
 import createAccount from '../creators/account-creator';
 import { dbQuery, SQL } from '../database/database';
 import { deleteAccount } from '../deleters/account-deleters';
 import { deleteCookie } from '../deleters/cookie-deleters';
 import { sendAccessRequestEmailToAshoat } from '../emails/access-request';
 import { fetchEntryInfos } from '../fetchers/entry-fetchers';
 import { fetchMessageInfos } from '../fetchers/message-fetchers';
 import { fetchThreadInfos } from '../fetchers/thread-fetchers';
 import {
   fetchKnownUserInfos,
   fetchLoggedInUserInfo,
 } from '../fetchers/user-fetchers';
 import {
   createNewAnonymousCookie,
   createNewUserCookie,
   setNewSession,
 } from '../session/cookies';
 import type { Viewer } from '../session/viewer';
 import {
   accountUpdater,
   checkAndSendVerificationEmail,
   checkAndSendPasswordResetEmail,
   updatePassword,
   updateUserSettings,
 } from '../updaters/account-updaters';
 import { userSubscriptionUpdater } from '../updaters/user-subscription-updaters';
 import { validateInput } from '../utils/validation-utils';
 import {
   entryQueryInputValidator,
   newEntryQueryInputValidator,
   normalizeCalendarQuery,
   verifyCalendarQueryThreadIDs,
 } from './entry-responders';
 
 const subscriptionUpdateRequestInputValidator = tShape({
   threadID: t.String,
   updatedFields: tShape({
     pushNotifs: t.maybe(t.Boolean),
     home: t.maybe(t.Boolean),
   }),
 });
 
 async function userSubscriptionUpdateResponder(
   viewer: Viewer,
   input: any,
 ): Promise<SubscriptionUpdateResponse> {
   const request: SubscriptionUpdateRequest = input;
   await validateInput(viewer, subscriptionUpdateRequestInputValidator, request);
   const threadSubscription = await userSubscriptionUpdater(viewer, request);
   return { threadSubscription };
 }
 
 const accountUpdateInputValidator = tShape({
   updatedFields: tShape({
     email: t.maybe(tEmail),
     password: t.maybe(tPassword),
   }),
   currentPassword: tPassword,
 });
 
 async function passwordUpdateResponder(
   viewer: Viewer,
   input: any,
 ): Promise<void> {
   const request: PasswordUpdate = input;
   await validateInput(viewer, accountUpdateInputValidator, request);
   await accountUpdater(viewer, request);
 }
 
 async function sendVerificationEmailResponder(viewer: Viewer): Promise<void> {
   await validateInput(viewer, null, null);
   await checkAndSendVerificationEmail(viewer);
 }
 
 const resetPasswordRequestInputValidator = tShape({
   usernameOrEmail: t.union([tEmail, tOldValidUsername]),
 });
 
 async function sendPasswordResetEmailResponder(
   viewer: Viewer,
   input: any,
 ): Promise<void> {
   const request: ResetPasswordRequest = input;
   await validateInput(viewer, resetPasswordRequestInputValidator, request);
   await checkAndSendPasswordResetEmail(request);
 }
 
 async function logOutResponder(viewer: Viewer): Promise<LogOutResponse> {
   await validateInput(viewer, null, null);
   if (viewer.loggedIn) {
     const [anonymousViewerData] = await Promise.all([
       createNewAnonymousCookie({
         platformDetails: viewer.platformDetails,
         deviceToken: viewer.deviceToken,
       }),
       deleteCookie(viewer.cookieID),
     ]);
     viewer.setNewCookie(anonymousViewerData);
   }
   return {
     currentUserInfo: {
       id: viewer.id,
       anonymous: true,
     },
   };
 }
 
 const deleteAccountRequestInputValidator = tShape({
   password: tPassword,
 });
 
 async function accountDeletionResponder(
   viewer: Viewer,
   input: any,
 ): Promise<LogOutResponse> {
   const request: DeleteAccountRequest = input;
   await validateInput(viewer, deleteAccountRequestInputValidator, request);
   const result = await deleteAccount(viewer, request);
   invariant(result, 'deleteAccount should return result if handed request');
   return result;
 }
 
 const deviceTokenUpdateRequestInputValidator = tShape({
   deviceType: t.maybe(t.enums.of(['ios', 'android'])),
   deviceToken: t.String,
 });
 
 const registerRequestInputValidator = tShape({
   username: t.String,
   email: t.maybe(tEmail),
   password: tPassword,
   calendarQuery: t.maybe(newEntryQueryInputValidator),
   deviceTokenUpdateRequest: t.maybe(deviceTokenUpdateRequestInputValidator),
   platformDetails: tPlatformDetails,
 });
 
 async function accountCreationResponder(
   viewer: Viewer,
   input: any,
 ): Promise<RegisterResponse> {
   const request: RegisterRequest = input;
   await validateInput(viewer, registerRequestInputValidator, request);
   return await createAccount(viewer, request);
 }
 
 const logInRequestInputValidator = tShape({
   username: t.maybe(t.String),
   usernameOrEmail: t.maybe(t.union([tEmail, tOldValidUsername])),
   password: tPassword,
   watchedIDs: t.list(t.String),
   calendarQuery: t.maybe(entryQueryInputValidator),
   deviceTokenUpdateRequest: t.maybe(deviceTokenUpdateRequestInputValidator),
   platformDetails: tPlatformDetails,
 });
 
 async function logInResponder(
   viewer: Viewer,
   input: any,
 ): Promise<LogInResponse> {
   await validateInput(viewer, logInRequestInputValidator, input);
   const request: LogInRequest = input;
 
   const calendarQuery = request.calendarQuery
     ? normalizeCalendarQuery(request.calendarQuery)
     : null;
   const promises = {};
   if (calendarQuery) {
     promises.verifyCalendarQueryThreadIDs = verifyCalendarQueryThreadIDs(
       calendarQuery,
     );
   }
   const username = request.username ?? request.usernameOrEmail;
   if (!username) {
     throw new ServerError('invalid_parameters');
   }
   const userQuery = SQL`
     SELECT id, hash, username
     FROM users
     WHERE LCASE(username) = LCASE(${username})
   `;
   promises.userQuery = dbQuery(userQuery);
   const {
     userQuery: [userResult],
   } = await promiseAll(promises);
 
   if (userResult.length === 0) {
     throw new ServerError('invalid_parameters');
   }
   const userRow = userResult[0];
   if (!userRow.hash || !bcrypt.compareSync(request.password, userRow.hash)) {
     throw new ServerError('invalid_credentials');
   }
   const id = userRow.id.toString();
 
   const newServerTime = Date.now();
   const deviceToken = request.deviceTokenUpdateRequest
     ? request.deviceTokenUpdateRequest.deviceToken
     : viewer.deviceToken;
   const [userViewerData] = await Promise.all([
     createNewUserCookie(id, {
       platformDetails: request.platformDetails,
       deviceToken,
     }),
     deleteCookie(viewer.cookieID),
   ]);
   viewer.setNewCookie(userViewerData);
   if (calendarQuery) {
     await setNewSession(viewer, calendarQuery, newServerTime);
   }
 
   const threadCursors = {};
   for (const watchedThreadID of request.watchedIDs) {
     threadCursors[watchedThreadID] = null;
   }
-  const threadSelectionCriteria = { threadCursors, joinedThreads: true };
+  const messageSelectionCriteria = { threadCursors, joinedThreads: true };
 
   const [
     threadsResult,
     messagesResult,
     entriesResult,
     userInfos,
     currentUserInfo,
   ] = await Promise.all([
     fetchThreadInfos(viewer),
-    fetchMessageInfos(viewer, threadSelectionCriteria, defaultNumberPerThread),
+    fetchMessageInfos(viewer, messageSelectionCriteria, defaultNumberPerThread),
     calendarQuery ? fetchEntryInfos(viewer, [calendarQuery]) : undefined,
     fetchKnownUserInfos(viewer),
     fetchLoggedInUserInfo(viewer),
   ]);
 
   const rawEntryInfos = entriesResult ? entriesResult.rawEntryInfos : null;
   const response: LogInResponse = {
     currentUserInfo,
     rawMessageInfos: messagesResult.rawMessageInfos,
     truncationStatuses: messagesResult.truncationStatuses,
     serverTime: newServerTime,
     userInfos: values(userInfos),
     cookieChange: {
       threadInfos: threadsResult.threadInfos,
       userInfos: [],
     },
   };
   if (rawEntryInfos) {
     response.rawEntryInfos = rawEntryInfos;
   }
   return response;
 }
 
 const updatePasswordRequestInputValidator = tShape({
   code: t.String,
   password: tPassword,
   watchedIDs: t.list(t.String),
   calendarQuery: t.maybe(entryQueryInputValidator),
   deviceTokenUpdateRequest: t.maybe(deviceTokenUpdateRequestInputValidator),
   platformDetails: tPlatformDetails,
 });
 
 async function oldPasswordUpdateResponder(
   viewer: Viewer,
   input: any,
 ): Promise<LogInResponse> {
   await validateInput(viewer, updatePasswordRequestInputValidator, input);
   const request: UpdatePasswordRequest = input;
   if (request.calendarQuery) {
     request.calendarQuery = normalizeCalendarQuery(request.calendarQuery);
   }
   return await updatePassword(viewer, request);
 }
 
 const accessRequestInputValidator = tShape({
   email: tEmail,
   platform: tDeviceType,
 });
 
 async function requestAccessResponder(
   viewer: Viewer,
   input: any,
 ): Promise<void> {
   const request: AccessRequest = input;
   await validateInput(viewer, accessRequestInputValidator, request);
 
   await sendAccessRequestEmailToAshoat(request);
 }
 
 const updateUserSettingsInputValidator = tShape({
   name: t.irreducible(
     userSettingsTypes.DEFAULT_NOTIFICATIONS,
     x => x === userSettingsTypes.DEFAULT_NOTIFICATIONS,
   ),
   data: t.enums.of(notificationTypeValues),
 });
 
 async function updateUserSettingsResponder(
   viewer: Viewer,
   input: any,
 ): Promise<void> {
   const request: UpdateUserSettingsRequest = input;
   await validateInput(viewer, updateUserSettingsInputValidator, request);
   return await updateUserSettings(viewer, request);
 }
 
 export {
   userSubscriptionUpdateResponder,
   passwordUpdateResponder,
   sendVerificationEmailResponder,
   sendPasswordResetEmailResponder,
   logOutResponder,
   accountDeletionResponder,
   accountCreationResponder,
   logInResponder,
   oldPasswordUpdateResponder,
   requestAccessResponder,
   updateUserSettingsResponder,
 };
diff --git a/server/src/responders/website-responders.js b/server/src/responders/website-responders.js
index b5ddcfe92..62855ea40 100644
--- a/server/src/responders/website-responders.js
+++ b/server/src/responders/website-responders.js
@@ -1,336 +1,336 @@
 // @flow
 
 import html from 'common-tags/lib/html';
 import type { $Response, $Request } from 'express';
 import fs from 'fs';
 import _keyBy from 'lodash/fp/keyBy';
 import * as React from 'react';
 import ReactDOMServer from 'react-dom/server';
 import { Provider } from 'react-redux';
 import { Route, StaticRouter } from 'react-router';
 import { createStore, type Store } from 'redux';
 import { promisify } from 'util';
 
 import { daysToEntriesFromEntryInfos } from 'lib/reducers/entry-reducer';
 import { freshMessageStore } from 'lib/reducers/message-reducer';
 import { mostRecentReadThread } from 'lib/selectors/thread-selectors';
 import { mostRecentMessageTimestamp } from 'lib/shared/message-utils';
 import { threadHasPermission } from 'lib/shared/thread-utils';
 import { defaultWebEnabledApps } from 'lib/types/enabled-apps';
 import { defaultCalendarFilters } from 'lib/types/filter-types';
 import { defaultNumberPerThread } from 'lib/types/message-types';
 import { defaultEnabledReports } from 'lib/types/report-types';
 import { defaultConnectionInfo } from 'lib/types/socket-types';
 import { threadPermissions } from 'lib/types/thread-types';
 import type { CurrentUserInfo } from 'lib/types/user-types';
 import { currentDateInTimeZone } from 'lib/utils/date-utils';
 import { ServerError } from 'lib/utils/errors';
 import { promiseAll } from 'lib/utils/promises';
 import { reducer } from 'web/redux/redux-setup';
 import type { AppState, Action } from 'web/redux/redux-setup';
 import getTitle from 'web/title/getTitle';
 import { navInfoFromURL } from 'web/url-utils';
 
 import { fetchEntryInfos } from '../fetchers/entry-fetchers';
 import { fetchMessageInfos } from '../fetchers/message-fetchers';
 import { fetchThreadInfos } from '../fetchers/thread-fetchers';
 import {
   fetchCurrentUserInfo,
   fetchKnownUserInfos,
 } from '../fetchers/user-fetchers';
 import { setNewSession } from '../session/cookies';
 import { Viewer } from '../session/viewer';
 import { streamJSON, waitForStream } from '../utils/json-stream';
 import { getAppURLFacts } from '../utils/urls';
 
 const { basePath, baseDomain } = getAppURLFacts();
 const { renderToNodeStream } = ReactDOMServer;
 
 const baseURL = basePath.replace(/\/$/, '');
 const baseHref = baseDomain + baseURL;
 
 const access = promisify(fs.access);
 const googleFontsURL =
   'https://fonts.googleapis.com/css2?family=IBM+Plex+Sans:wght@400;500;600&family=Inter:wght@400;500;600&display=swap';
 const localFontsURL = 'fonts/local-fonts.css';
 async function getFontsURL() {
   try {
     await access(localFontsURL);
     return localFontsURL;
   } catch {
     return googleFontsURL;
   }
 }
 
 type AssetInfo = { jsURL: string, fontsURL: string, cssInclude: string };
 let assetInfo: ?AssetInfo = null;
 async function getAssetInfo() {
   if (assetInfo) {
     return assetInfo;
   }
   if (process.env.NODE_ENV === 'development') {
     const fontsURL = await getFontsURL();
     assetInfo = {
       jsURL: 'http://localhost:8080/dev.build.js',
       fontsURL,
       cssInclude: '',
     };
     return assetInfo;
   }
   // $FlowFixMe web/dist doesn't always exist
   const { default: assets } = await import('web/dist/assets');
   assetInfo = {
     jsURL: `compiled/${assets.browser.js}`,
     fontsURL: googleFontsURL,
     cssInclude: html`
       <link
         rel="stylesheet"
         type="text/css"
         href="compiled/${assets.browser.css}"
       />
     `,
   };
   return assetInfo;
 }
 
 let webpackCompiledRootComponent: ?React.ComponentType<{}> = null;
 async function getWebpackCompiledRootComponentForSSR() {
   if (webpackCompiledRootComponent) {
     return webpackCompiledRootComponent;
   }
   try {
     // $FlowFixMe web/dist doesn't always exist
     const webpackBuild = await import('web/dist/app.build.cjs');
     webpackCompiledRootComponent = webpackBuild.default.default;
     return webpackCompiledRootComponent;
   } catch {
     throw new Error(
       'Could not load app.build.cjs. ' +
         'Did you forget to run `yarn dev` in the web folder?',
     );
   }
 }
 
 async function websiteResponder(
   viewer: Viewer,
   req: $Request,
   res: $Response,
 ): Promise<void> {
   const appPromise = getWebpackCompiledRootComponentForSSR();
 
   let initialNavInfo;
   try {
     initialNavInfo = navInfoFromURL(req.url, {
       now: currentDateInTimeZone(viewer.timeZone),
     });
   } catch (e) {
     throw new ServerError(e.message);
   }
 
   const calendarQuery = {
     startDate: initialNavInfo.startDate,
     endDate: initialNavInfo.endDate,
     filters: defaultCalendarFilters,
   };
-  const threadSelectionCriteria = { joinedThreads: true };
+  const messageSelectionCriteria = { joinedThreads: true };
   const initialTime = Date.now();
 
   const assetInfoPromise = getAssetInfo();
   const threadInfoPromise = fetchThreadInfos(viewer);
   const messageInfoPromise = fetchMessageInfos(
     viewer,
-    threadSelectionCriteria,
+    messageSelectionCriteria,
     defaultNumberPerThread,
   );
   const entryInfoPromise = fetchEntryInfos(viewer, [calendarQuery]);
   const currentUserInfoPromise = fetchCurrentUserInfo(viewer);
   const userInfoPromise = fetchKnownUserInfos(viewer);
 
   const sessionIDPromise = (async () => {
     if (viewer.loggedIn) {
       await setNewSession(viewer, calendarQuery, initialTime);
     }
     return viewer.sessionID;
   })();
 
   const threadStorePromise = (async () => {
     const { threadInfos } = await threadInfoPromise;
     return { threadInfos };
   })();
   const messageStorePromise = (async () => {
     const [
       { threadInfos },
       { rawMessageInfos, truncationStatuses },
     ] = await Promise.all([threadInfoPromise, messageInfoPromise]);
     const { messageStore: freshStore } = freshMessageStore(
       rawMessageInfos,
       truncationStatuses,
       mostRecentMessageTimestamp(rawMessageInfos, initialTime),
       threadInfos,
     );
     return freshStore;
   })();
   const entryStorePromise = (async () => {
     const { rawEntryInfos } = await entryInfoPromise;
     return {
       entryInfos: _keyBy('id')(rawEntryInfos),
       daysToEntries: daysToEntriesFromEntryInfos(rawEntryInfos),
       lastUserInteractionCalendar: initialTime,
     };
   })();
   const userStorePromise = (async () => {
     const userInfos = await userInfoPromise;
     return { userInfos, inconsistencyReports: [] };
   })();
 
   const navInfoPromise = (async () => {
     const [{ threadInfos }, messageStore] = await Promise.all([
       threadInfoPromise,
       messageStorePromise,
     ]);
     const finalNavInfo = initialNavInfo;
 
     const requestedActiveChatThreadID = finalNavInfo.activeChatThreadID;
     if (
       requestedActiveChatThreadID &&
       !threadHasPermission(
         threadInfos[requestedActiveChatThreadID],
         threadPermissions.VISIBLE,
       )
     ) {
       finalNavInfo.activeChatThreadID = null;
     }
 
     if (!finalNavInfo.activeChatThreadID) {
       const mostRecentThread = mostRecentReadThread(messageStore, threadInfos);
       if (mostRecentThread) {
         finalNavInfo.activeChatThreadID = mostRecentThread;
       }
     }
 
     return finalNavInfo;
   })();
 
   const { jsURL, fontsURL, cssInclude } = await assetInfoPromise;
 
   // prettier-ignore
   res.write(html`
     <!DOCTYPE html>
     <html lang="en">
       <head>
         <meta charset="utf-8" />
         <title>${getTitle(0)}</title>
         <base href="${basePath}" />
         <link rel="stylesheet" type="text/css" href="${fontsURL}" />
         ${cssInclude}
         <link
           rel="apple-touch-icon"
           sizes="180x180"
           href="apple-touch-icon.png"
         />
         <link
           rel="icon"
           type="image/png"
           sizes="32x32"
           href="favicon-32x32.png"
         />
         <link
           rel="icon"
           type="image/png"
           sizes="16x16"
           href="favicon-16x16.png"
         />
         <link rel="manifest" href="site.webmanifest" />
         <link rel="mask-icon" href="safari-pinned-tab.svg" color="#b91d47" />
         <meta name="apple-mobile-web-app-title" content="Comm" />
         <meta name="application-name" content="Comm" />
         <meta name="msapplication-TileColor" content="#b91d47" />
         <meta name="theme-color" content="#b91d47" />
       </head>
       <body>
         <div id="react-root">
   `);
 
   const statePromises = {
     navInfo: navInfoPromise,
     currentUserInfo: ((currentUserInfoPromise: any): Promise<CurrentUserInfo>),
     sessionID: sessionIDPromise,
     entryStore: entryStorePromise,
     threadStore: threadStorePromise,
     userStore: userStorePromise,
     messageStore: messageStorePromise,
     updatesCurrentAsOf: initialTime,
     loadingStatuses: {},
     calendarFilters: defaultCalendarFilters,
     // We can use paths local to the <base href> on web
     urlPrefix: '',
     windowDimensions: { width: 0, height: 0 },
     baseHref,
     connection: {
       ...defaultConnectionInfo('web', viewer.timeZone),
       actualizedCalendarQuery: calendarQuery,
     },
     watchedThreadIDs: [],
     lifecycleState: 'active',
     enabledApps: defaultWebEnabledApps,
     reportStore: {
       enabledReports: defaultEnabledReports,
       queuedReports: [],
     },
     nextLocalID: 0,
     timeZone: viewer.timeZone,
     userAgent: viewer.userAgent,
     cookie: undefined,
     deviceToken: undefined,
     dataLoaded: viewer.loggedIn,
     windowActive: true,
   };
 
   const [stateResult, App] = await Promise.all([
     promiseAll(statePromises),
     appPromise,
   ]);
   const state: AppState = { ...stateResult };
   const store: Store<AppState, Action> = createStore(reducer, state);
 
   const routerContext = {};
   const reactStream = renderToNodeStream(
     <Provider store={store}>
       <StaticRouter
         location={req.url}
         basename={baseURL}
         context={routerContext}
       >
         <Route path="*" component={App} />
       </StaticRouter>
     </Provider>,
   );
   if (routerContext.url) {
     throw new ServerError('URL modified during server render!');
   }
   reactStream.pipe(res, { end: false });
   await waitForStream(reactStream);
   res.write(html`
     </div>
     <script>
       var preloadedState =
   `);
 
   const filteredStatePromises = {
     ...statePromises,
     timeZone: null,
     userAgent: null,
   };
   const jsonStream = streamJSON(res, filteredStatePromises);
   await waitForStream(jsonStream);
   res.end(html`
     ;
           var baseURL = "${baseURL}";
         </script>
         <script src="${jsURL}"></script>
       </body>
     </html>
   `);
 }
 
 export { websiteResponder };
diff --git a/server/src/socket/socket.js b/server/src/socket/socket.js
index 14280f02f..9aab1a7dc 100644
--- a/server/src/socket/socket.js
+++ b/server/src/socket/socket.js
@@ -1,810 +1,810 @@
 // @flow
 
 import type { $Request } from 'express';
 import invariant from 'invariant';
 import _debounce from 'lodash/debounce';
 import t from 'tcomb';
 import WebSocket from 'ws';
 
 import { mostRecentMessageTimestamp } from 'lib/shared/message-utils';
 import {
   serverRequestSocketTimeout,
   serverResponseTimeout,
 } from 'lib/shared/timeouts';
 import { mostRecentUpdateTimestamp } from 'lib/shared/update-utils';
 import type { Shape } from 'lib/types/core';
 import { endpointIsSocketSafe } from 'lib/types/endpoints';
 import { defaultNumberPerThread } from 'lib/types/message-types';
 import { redisMessageTypes, type RedisMessage } from 'lib/types/redis-types';
 import {
   cookieSources,
   sessionCheckFrequency,
   stateCheckInactivityActivationInterval,
 } from 'lib/types/session-types';
 import {
   type ClientSocketMessage,
   type InitialClientSocketMessage,
   type ResponsesClientSocketMessage,
   type ServerStateSyncFullSocketPayload,
   type ServerServerSocketMessage,
   type ErrorServerSocketMessage,
   type AuthErrorServerSocketMessage,
   type PingClientSocketMessage,
   type AckUpdatesClientSocketMessage,
   type APIRequestClientSocketMessage,
   clientSocketMessageTypes,
   stateSyncPayloadTypes,
   serverSocketMessageTypes,
 } from 'lib/types/socket-types';
 import { ServerError } from 'lib/utils/errors';
 import { values } from 'lib/utils/objects';
 import { promiseAll } from 'lib/utils/promises';
 import SequentialPromiseResolver from 'lib/utils/sequential-promise-resolver';
 import sleep from 'lib/utils/sleep';
 import { tShape, tCookie } from 'lib/utils/validation-utils';
 
 import { fetchUpdateInfosWithRawUpdateInfos } from '../creators/update-creator';
 import { deleteActivityForViewerSession } from '../deleters/activity-deleters';
 import { deleteCookie } from '../deleters/cookie-deleters';
 import { deleteUpdatesBeforeTimeTargetingSession } from '../deleters/update-deleters';
 import { jsonEndpoints } from '../endpoints';
 import { fetchEntryInfos } from '../fetchers/entry-fetchers';
 import {
   fetchMessageInfosSince,
   getMessageFetchResultFromRedisMessages,
 } from '../fetchers/message-fetchers';
 import { fetchThreadInfos } from '../fetchers/thread-fetchers';
 import { fetchUpdateInfos } from '../fetchers/update-fetchers';
 import {
   fetchCurrentUserInfo,
   fetchKnownUserInfos,
 } from '../fetchers/user-fetchers';
 import {
   newEntryQueryInputValidator,
   verifyCalendarQueryThreadIDs,
 } from '../responders/entry-responders';
 import { handleAsyncPromise } from '../responders/handlers';
 import {
   fetchViewerForSocket,
   extendCookieLifespan,
   createNewAnonymousCookie,
 } from '../session/cookies';
 import { Viewer } from '../session/viewer';
 import { commitSessionUpdate } from '../updaters/session-updaters';
 import { assertSecureRequest } from '../utils/security-utils';
 import {
   checkInputValidator,
   checkClientSupported,
 } from '../utils/validation-utils';
 import { RedisSubscriber } from './redis';
 import {
   clientResponseInputValidator,
   processClientResponses,
   initializeSession,
   checkState,
 } from './session-utils';
 
 const clientSocketMessageInputValidator = t.union([
   tShape({
     type: t.irreducible(
       'clientSocketMessageTypes.INITIAL',
       x => x === clientSocketMessageTypes.INITIAL,
     ),
     id: t.Number,
     payload: tShape({
       sessionIdentification: tShape({
         cookie: t.maybe(tCookie),
         sessionID: t.maybe(t.String),
       }),
       sessionState: tShape({
         calendarQuery: newEntryQueryInputValidator,
         messagesCurrentAsOf: t.Number,
         updatesCurrentAsOf: t.Number,
         watchedIDs: t.list(t.String),
       }),
       clientResponses: t.list(clientResponseInputValidator),
     }),
   }),
   tShape({
     type: t.irreducible(
       'clientSocketMessageTypes.RESPONSES',
       x => x === clientSocketMessageTypes.RESPONSES,
     ),
     id: t.Number,
     payload: tShape({
       clientResponses: t.list(clientResponseInputValidator),
     }),
   }),
   tShape({
     type: t.irreducible(
       'clientSocketMessageTypes.PING',
       x => x === clientSocketMessageTypes.PING,
     ),
     id: t.Number,
   }),
   tShape({
     type: t.irreducible(
       'clientSocketMessageTypes.ACK_UPDATES',
       x => x === clientSocketMessageTypes.ACK_UPDATES,
     ),
     id: t.Number,
     payload: tShape({
       currentAsOf: t.Number,
     }),
   }),
   tShape({
     type: t.irreducible(
       'clientSocketMessageTypes.API_REQUEST',
       x => x === clientSocketMessageTypes.API_REQUEST,
     ),
     id: t.Number,
     payload: tShape({
       endpoint: t.String,
       input: t.Object,
     }),
   }),
 ]);
 
 function onConnection(ws: WebSocket, req: $Request) {
   assertSecureRequest(req);
   new Socket(ws, req);
 }
 
 type StateCheckConditions = {
   activityRecentlyOccurred: boolean,
   stateCheckOngoing: boolean,
 };
 
 class Socket {
   ws: WebSocket;
   httpRequest: $Request;
   viewer: ?Viewer;
   redis: ?RedisSubscriber;
   redisPromiseResolver: SequentialPromiseResolver<ServerServerSocketMessage>;
 
   stateCheckConditions: StateCheckConditions = {
     activityRecentlyOccurred: true,
     stateCheckOngoing: false,
   };
   stateCheckTimeoutID: ?TimeoutID;
 
   constructor(ws: WebSocket, httpRequest: $Request) {
     this.ws = ws;
     this.httpRequest = httpRequest;
     ws.on('message', this.onMessage);
     ws.on('close', this.onClose);
     this.resetTimeout();
     this.redisPromiseResolver = new SequentialPromiseResolver(this.sendMessage);
   }
 
   onMessage = async (
     messageString: string | Buffer | ArrayBuffer | Array<Buffer>,
   ) => {
     invariant(typeof messageString === 'string', 'message should be string');
     let clientSocketMessage: ?ClientSocketMessage;
     try {
       this.resetTimeout();
       const message = JSON.parse(messageString);
       checkInputValidator(clientSocketMessageInputValidator, message);
       clientSocketMessage = message;
       if (clientSocketMessage.type === clientSocketMessageTypes.INITIAL) {
         if (this.viewer) {
           // This indicates that the user sent multiple INITIAL messages.
           throw new ServerError('socket_already_initialized');
         }
         this.viewer = await fetchViewerForSocket(
           this.httpRequest,
           clientSocketMessage,
         );
         if (!this.viewer) {
           // This indicates that the cookie was invalid, but the client is using
           // cookieSources.HEADER and thus can't accept a new cookie over
           // WebSockets. See comment under catch block for socket_deauthorized.
           throw new ServerError('socket_deauthorized');
         }
       }
       const { viewer } = this;
       if (!viewer) {
         // This indicates a non-INITIAL message was sent by the client before
         // the INITIAL message.
         throw new ServerError('socket_uninitialized');
       }
       if (viewer.sessionChanged) {
         // This indicates that the cookie was invalid, and we've assigned a new
         // anonymous one.
         throw new ServerError('socket_deauthorized');
       }
       if (!viewer.loggedIn) {
         // This indicates that the specified cookie was an anonymous one.
         throw new ServerError('not_logged_in');
       }
       await checkClientSupported(
         viewer,
         clientSocketMessageInputValidator,
         clientSocketMessage,
       );
       const serverResponses = await this.handleClientSocketMessage(
         clientSocketMessage,
       );
       if (!this.redis) {
         this.redis = new RedisSubscriber(
           { userID: viewer.userID, sessionID: viewer.session },
           this.onRedisMessage,
         );
       }
       if (viewer.sessionChanged) {
         // This indicates that something has caused the session to change, which
         // shouldn't happen from inside a WebSocket since we can't handle cookie
         // invalidation.
         throw new ServerError('session_mutated_from_socket');
       }
       if (clientSocketMessage.type !== clientSocketMessageTypes.PING) {
         handleAsyncPromise(extendCookieLifespan(viewer.cookieID));
       }
       for (const response of serverResponses) {
         this.sendMessage(response);
       }
       if (clientSocketMessage.type === clientSocketMessageTypes.INITIAL) {
         this.onSuccessfulConnection();
       }
     } catch (error) {
       console.warn(error);
       if (!(error instanceof ServerError)) {
         const errorMessage: ErrorServerSocketMessage = {
           type: serverSocketMessageTypes.ERROR,
           message: error.message,
         };
         const responseTo = clientSocketMessage ? clientSocketMessage.id : null;
         if (responseTo !== null) {
           errorMessage.responseTo = responseTo;
         }
         this.markActivityOccurred();
         this.sendMessage(errorMessage);
         return;
       }
       invariant(clientSocketMessage, 'should be set');
       const responseTo = clientSocketMessage.id;
       if (error.message === 'socket_deauthorized') {
         const authErrorMessage: AuthErrorServerSocketMessage = {
           type: serverSocketMessageTypes.AUTH_ERROR,
           responseTo,
           message: error.message,
         };
         if (this.viewer) {
           // viewer should only be falsey for cookieSources.HEADER (web)
           // clients. Usually if the cookie is invalid we construct a new
           // anonymous Viewer with a new cookie, and then pass the cookie down
           // in the error. But we can't pass HTTP cookies in WebSocket messages.
           authErrorMessage.sessionChange = {
             cookie: this.viewer.cookiePairString,
             currentUserInfo: {
               id: this.viewer.cookieID,
               anonymous: true,
             },
           };
         }
         this.sendMessage(authErrorMessage);
         this.ws.close(4100, error.message);
         return;
       } else if (error.message === 'client_version_unsupported') {
         const { viewer } = this;
         invariant(viewer, 'should be set');
         const promises = {};
         promises.deleteCookie = deleteCookie(viewer.cookieID);
         if (viewer.cookieSource !== cookieSources.BODY) {
           promises.anonymousViewerData = createNewAnonymousCookie({
             platformDetails: error.platformDetails,
             deviceToken: viewer.deviceToken,
           });
         }
         const { anonymousViewerData } = await promiseAll(promises);
         const authErrorMessage: AuthErrorServerSocketMessage = {
           type: serverSocketMessageTypes.AUTH_ERROR,
           responseTo,
           message: error.message,
         };
         if (anonymousViewerData) {
           // It is normally not safe to pass the result of
           // createNewAnonymousCookie to the Viewer constructor. That is because
           // createNewAnonymousCookie leaves several fields of
           // AnonymousViewerData unset, and consequently Viewer will throw when
           // access is attempted. It is only safe here because we can guarantee
           // that only cookiePairString and cookieID are accessed on anonViewer
           // below.
           const anonViewer = new Viewer(anonymousViewerData);
           authErrorMessage.sessionChange = {
             cookie: anonViewer.cookiePairString,
             currentUserInfo: {
               id: anonViewer.cookieID,
               anonymous: true,
             },
           };
         }
         this.sendMessage(authErrorMessage);
         this.ws.close(4101, error.message);
         return;
       }
       if (error.payload) {
         this.sendMessage({
           type: serverSocketMessageTypes.ERROR,
           responseTo,
           message: error.message,
           payload: error.payload,
         });
       } else {
         this.sendMessage({
           type: serverSocketMessageTypes.ERROR,
           responseTo,
           message: error.message,
         });
       }
       if (error.message === 'not_logged_in') {
         this.ws.close(4102, error.message);
       } else if (error.message === 'session_mutated_from_socket') {
         this.ws.close(4103, error.message);
       } else {
         this.markActivityOccurred();
       }
     }
   };
 
   onClose = async () => {
     this.clearStateCheckTimeout();
     this.resetTimeout.cancel();
     this.debouncedAfterActivity.cancel();
     if (this.viewer && this.viewer.hasSessionInfo) {
       await deleteActivityForViewerSession(this.viewer);
     }
     if (this.redis) {
       this.redis.quit();
       this.redis = null;
     }
   };
 
   sendMessage = (message: ServerServerSocketMessage) => {
     invariant(
       this.ws.readyState > 0,
       "shouldn't send message until connection established",
     );
     if (this.ws.readyState === 1) {
       this.ws.send(JSON.stringify(message));
     }
   };
 
   async handleClientSocketMessage(
     message: ClientSocketMessage,
   ): Promise<ServerServerSocketMessage[]> {
     const resultPromise = (async () => {
       if (message.type === clientSocketMessageTypes.INITIAL) {
         this.markActivityOccurred();
         return await this.handleInitialClientSocketMessage(message);
       } else if (message.type === clientSocketMessageTypes.RESPONSES) {
         this.markActivityOccurred();
         return await this.handleResponsesClientSocketMessage(message);
       } else if (message.type === clientSocketMessageTypes.PING) {
         return this.handlePingClientSocketMessage(message);
       } else if (message.type === clientSocketMessageTypes.ACK_UPDATES) {
         this.markActivityOccurred();
         return await this.handleAckUpdatesClientSocketMessage(message);
       } else if (message.type === clientSocketMessageTypes.API_REQUEST) {
         this.markActivityOccurred();
         return await this.handleAPIRequestClientSocketMessage(message);
       }
       return [];
     })();
     const timeoutPromise = (async () => {
       await sleep(serverResponseTimeout);
       throw new ServerError('socket_response_timeout');
     })();
     return await Promise.race([resultPromise, timeoutPromise]);
   }
 
   async handleInitialClientSocketMessage(
     message: InitialClientSocketMessage,
   ): Promise<ServerServerSocketMessage[]> {
     const { viewer } = this;
     invariant(viewer, 'should be set');
 
     const responses = [];
 
     const { sessionState, clientResponses } = message.payload;
     const {
       calendarQuery,
       updatesCurrentAsOf: oldUpdatesCurrentAsOf,
       messagesCurrentAsOf: oldMessagesCurrentAsOf,
       watchedIDs,
     } = sessionState;
     await verifyCalendarQueryThreadIDs(calendarQuery);
 
     const sessionInitializationResult = await initializeSession(
       viewer,
       calendarQuery,
       oldUpdatesCurrentAsOf,
     );
 
     const threadCursors = {};
     for (const watchedThreadID of watchedIDs) {
       threadCursors[watchedThreadID] = null;
     }
-    const threadSelectionCriteria = { threadCursors, joinedThreads: true };
+    const messageSelectionCriteria = { threadCursors, joinedThreads: true };
     const [
       fetchMessagesResult,
       { serverRequests, activityUpdateResult },
     ] = await Promise.all([
       fetchMessageInfosSince(
         viewer,
-        threadSelectionCriteria,
+        messageSelectionCriteria,
         oldMessagesCurrentAsOf,
         defaultNumberPerThread,
       ),
       processClientResponses(viewer, clientResponses),
     ]);
     const messagesResult = {
       rawMessageInfos: fetchMessagesResult.rawMessageInfos,
       truncationStatuses: fetchMessagesResult.truncationStatuses,
       currentAsOf: mostRecentMessageTimestamp(
         fetchMessagesResult.rawMessageInfos,
         oldMessagesCurrentAsOf,
       ),
     };
 
     if (!sessionInitializationResult.sessionContinued) {
       const [
         threadsResult,
         entriesResult,
         currentUserInfo,
         knownUserInfos,
       ] = await Promise.all([
         fetchThreadInfos(viewer),
         fetchEntryInfos(viewer, [calendarQuery]),
         fetchCurrentUserInfo(viewer),
         fetchKnownUserInfos(viewer),
       ]);
       const payload: ServerStateSyncFullSocketPayload = {
         type: stateSyncPayloadTypes.FULL,
         messagesResult,
         threadInfos: threadsResult.threadInfos,
         currentUserInfo,
         rawEntryInfos: entriesResult.rawEntryInfos,
         userInfos: values(knownUserInfos),
         updatesCurrentAsOf: oldUpdatesCurrentAsOf,
       };
       if (viewer.sessionChanged) {
         // If initializeSession encounters sessionIdentifierTypes.BODY_SESSION_ID,
         // but the session is unspecified or expired, it will set a new sessionID
         // and specify viewer.sessionChanged
         const { sessionID } = viewer;
         invariant(
           sessionID !== null && sessionID !== undefined,
           'should be set',
         );
         payload.sessionID = sessionID;
         viewer.sessionChanged = false;
       }
       responses.push({
         type: serverSocketMessageTypes.STATE_SYNC,
         responseTo: message.id,
         payload,
       });
     } else {
       const {
         sessionUpdate,
         deltaEntryInfoResult,
       } = sessionInitializationResult;
 
       const promises = {};
       promises.deleteExpiredUpdates = deleteUpdatesBeforeTimeTargetingSession(
         viewer,
         oldUpdatesCurrentAsOf,
       );
       promises.fetchUpdateResult = fetchUpdateInfos(
         viewer,
         oldUpdatesCurrentAsOf,
         calendarQuery,
       );
       promises.sessionUpdate = commitSessionUpdate(viewer, sessionUpdate);
       const { fetchUpdateResult } = await promiseAll(promises);
 
       const { updateInfos, userInfos } = fetchUpdateResult;
       const newUpdatesCurrentAsOf = mostRecentUpdateTimestamp(
         [...updateInfos],
         oldUpdatesCurrentAsOf,
       );
       const updatesResult = {
         newUpdates: updateInfos,
         currentAsOf: newUpdatesCurrentAsOf,
       };
 
       responses.push({
         type: serverSocketMessageTypes.STATE_SYNC,
         responseTo: message.id,
         payload: {
           type: stateSyncPayloadTypes.INCREMENTAL,
           messagesResult,
           updatesResult,
           deltaEntryInfos: deltaEntryInfoResult.rawEntryInfos,
           deletedEntryIDs: deltaEntryInfoResult.deletedEntryIDs,
           userInfos: values(userInfos),
         },
       });
     }
 
     if (serverRequests.length > 0 || clientResponses.length > 0) {
       // We send this message first since the STATE_SYNC triggers the client's
       // connection status to shift to "connected", and we want to make sure the
       // client responses are cleared from Redux before that happens
       responses.unshift({
         type: serverSocketMessageTypes.REQUESTS,
         responseTo: message.id,
         payload: { serverRequests },
       });
     }
 
     if (activityUpdateResult) {
       // Same reason for unshifting as above
       responses.unshift({
         type: serverSocketMessageTypes.ACTIVITY_UPDATE_RESPONSE,
         responseTo: message.id,
         payload: activityUpdateResult,
       });
     }
 
     return responses;
   }
 
   async handleResponsesClientSocketMessage(
     message: ResponsesClientSocketMessage,
   ): Promise<ServerServerSocketMessage[]> {
     const { viewer } = this;
     invariant(viewer, 'should be set');
 
     const { clientResponses } = message.payload;
     const { stateCheckStatus } = await processClientResponses(
       viewer,
       clientResponses,
     );
 
     const serverRequests = [];
     if (stateCheckStatus && stateCheckStatus.status !== 'state_check') {
       const { sessionUpdate, checkStateRequest } = await checkState(
         viewer,
         stateCheckStatus,
         viewer.calendarQuery,
       );
       if (sessionUpdate) {
         await commitSessionUpdate(viewer, sessionUpdate);
         this.setStateCheckConditions({ stateCheckOngoing: false });
       }
       if (checkStateRequest) {
         serverRequests.push(checkStateRequest);
       }
     }
 
     // We send a response message regardless of whether we have any requests,
     // since we need to ack the client's responses
     return [
       {
         type: serverSocketMessageTypes.REQUESTS,
         responseTo: message.id,
         payload: { serverRequests },
       },
     ];
   }
 
   handlePingClientSocketMessage(
     message: PingClientSocketMessage,
   ): ServerServerSocketMessage[] {
     return [
       {
         type: serverSocketMessageTypes.PONG,
         responseTo: message.id,
       },
     ];
   }
 
   async handleAckUpdatesClientSocketMessage(
     message: AckUpdatesClientSocketMessage,
   ): Promise<ServerServerSocketMessage[]> {
     const { viewer } = this;
     invariant(viewer, 'should be set');
     const { currentAsOf } = message.payload;
     await Promise.all([
       deleteUpdatesBeforeTimeTargetingSession(viewer, currentAsOf),
       commitSessionUpdate(viewer, { lastUpdate: currentAsOf }),
     ]);
     return [];
   }
 
   async handleAPIRequestClientSocketMessage(
     message: APIRequestClientSocketMessage,
   ): Promise<ServerServerSocketMessage[]> {
     if (!endpointIsSocketSafe(message.payload.endpoint)) {
       throw new ServerError('endpoint_unsafe_for_socket');
     }
     const { viewer } = this;
     invariant(viewer, 'should be set');
     const responder = jsonEndpoints[message.payload.endpoint];
     const response = await responder(viewer, message.payload.input);
     return [
       {
         type: serverSocketMessageTypes.API_RESPONSE,
         responseTo: message.id,
         payload: response,
       },
     ];
   }
 
   onRedisMessage = async (message: RedisMessage) => {
     try {
       await this.processRedisMessage(message);
     } catch (e) {
       console.warn(e);
     }
   };
 
   async processRedisMessage(message: RedisMessage) {
     if (message.type === redisMessageTypes.START_SUBSCRIPTION) {
       this.ws.terminate();
     } else if (message.type === redisMessageTypes.NEW_UPDATES) {
       const { viewer } = this;
       invariant(viewer, 'should be set');
       if (message.ignoreSession && message.ignoreSession === viewer.session) {
         return;
       }
       const rawUpdateInfos = message.updates;
       this.redisPromiseResolver.add(
         (async () => {
           const {
             updateInfos,
             userInfos,
           } = await fetchUpdateInfosWithRawUpdateInfos(rawUpdateInfos, {
             viewer,
           });
           if (updateInfos.length === 0) {
             console.warn(
               'could not get any UpdateInfos from redisMessageTypes.NEW_UPDATES',
             );
             return null;
           }
           this.markActivityOccurred();
           return {
             type: serverSocketMessageTypes.UPDATES,
             payload: {
               updatesResult: {
                 currentAsOf: mostRecentUpdateTimestamp([...updateInfos], 0),
                 newUpdates: updateInfos,
               },
               userInfos: values(userInfos),
             },
           };
         })(),
       );
     } else if (message.type === redisMessageTypes.NEW_MESSAGES) {
       const { viewer } = this;
       invariant(viewer, 'should be set');
       const rawMessageInfos = message.messages;
       const messageFetchResult = getMessageFetchResultFromRedisMessages(
         viewer,
         rawMessageInfos,
       );
       if (messageFetchResult.rawMessageInfos.length === 0) {
         console.warn(
           'could not get any rawMessageInfos from ' +
             'redisMessageTypes.NEW_MESSAGES',
         );
         return;
       }
       this.redisPromiseResolver.add(
         (async () => {
           this.markActivityOccurred();
           return {
             type: serverSocketMessageTypes.MESSAGES,
             payload: {
               messagesResult: {
                 rawMessageInfos: messageFetchResult.rawMessageInfos,
                 truncationStatuses: messageFetchResult.truncationStatuses,
                 currentAsOf: mostRecentMessageTimestamp(
                   messageFetchResult.rawMessageInfos,
                   0,
                 ),
               },
             },
           };
         })(),
       );
     }
   }
 
   onSuccessfulConnection() {
     if (this.ws.readyState !== 1) {
       return;
     }
     this.handleStateCheckConditionsUpdate();
   }
 
   // The Socket will timeout by calling this.ws.terminate()
   // serverRequestSocketTimeout milliseconds after the last
   // time resetTimeout is called
   resetTimeout = _debounce(
     () => this.ws.terminate(),
     serverRequestSocketTimeout,
   );
 
   debouncedAfterActivity = _debounce(
     () => this.setStateCheckConditions({ activityRecentlyOccurred: false }),
     stateCheckInactivityActivationInterval,
   );
 
   markActivityOccurred = () => {
     if (this.ws.readyState !== 1) {
       return;
     }
     this.setStateCheckConditions({ activityRecentlyOccurred: true });
     this.debouncedAfterActivity();
   };
 
   clearStateCheckTimeout() {
     const { stateCheckTimeoutID } = this;
     if (stateCheckTimeoutID) {
       clearTimeout(stateCheckTimeoutID);
       this.stateCheckTimeoutID = null;
     }
   }
 
   setStateCheckConditions(newConditions: Shape<StateCheckConditions>) {
     this.stateCheckConditions = {
       ...this.stateCheckConditions,
       ...newConditions,
     };
     this.handleStateCheckConditionsUpdate();
   }
 
   get stateCheckCanStart() {
     return Object.values(this.stateCheckConditions).every(cond => !cond);
   }
 
   handleStateCheckConditionsUpdate() {
     if (!this.stateCheckCanStart) {
       this.clearStateCheckTimeout();
       return;
     }
     if (this.stateCheckTimeoutID) {
       return;
     }
     const { viewer } = this;
     if (!viewer) {
       return;
     }
     const timeUntilStateCheck =
       viewer.sessionLastValidated + sessionCheckFrequency - Date.now();
     if (timeUntilStateCheck <= 0) {
       this.initiateStateCheck();
     } else {
       this.stateCheckTimeoutID = setTimeout(
         this.initiateStateCheck,
         timeUntilStateCheck,
       );
     }
   }
 
   initiateStateCheck = async () => {
     this.setStateCheckConditions({ stateCheckOngoing: true });
 
     const { viewer } = this;
     invariant(viewer, 'should be set');
 
     const { checkStateRequest } = await checkState(
       viewer,
       { status: 'state_check' },
       viewer.calendarQuery,
     );
     invariant(checkStateRequest, 'should be set');
 
     this.sendMessage({
       type: serverSocketMessageTypes.REQUESTS,
       payload: { serverRequests: [checkStateRequest] },
     });
   };
 }
 
 export { onConnection };
diff --git a/server/src/updaters/thread-updaters.js b/server/src/updaters/thread-updaters.js
index 2c694aefa..f1c47e290 100644
--- a/server/src/updaters/thread-updaters.js
+++ b/server/src/updaters/thread-updaters.js
@@ -1,841 +1,841 @@
 // @flow
 
 import { filteredThreadIDs } from 'lib/selectors/calendar-filter-selectors';
 import {
   threadHasAdminRole,
   roleIsAdminRole,
   viewerIsMember,
   getThreadTypeParentRequirement,
 } from 'lib/shared/thread-utils';
 import { hasMinCodeVersion } from 'lib/shared/version-utils';
 import type { Shape } from 'lib/types/core';
 import { messageTypes, defaultNumberPerThread } from 'lib/types/message-types';
 import {
   type RoleChangeRequest,
   type ChangeThreadSettingsResult,
   type RemoveMembersRequest,
   type LeaveThreadRequest,
   type LeaveThreadResult,
   type UpdateThreadRequest,
   type ServerThreadJoinRequest,
   type ThreadJoinResult,
   threadPermissions,
   threadTypes,
 } from 'lib/types/thread-types';
 import { updateTypes } from 'lib/types/update-types';
 import { ServerError } from 'lib/utils/errors';
 import { promiseAll } from 'lib/utils/promises';
 import { firstLine } from 'lib/utils/string-utils';
 
 import createMessages from '../creators/message-creator';
 import { getRolePermissionBlobs } from '../creators/role-creator';
 import { createUpdates } from '../creators/update-creator';
 import { dbQuery, SQL } from '../database/database';
 import { fetchEntryInfos } from '../fetchers/entry-fetchers';
 import { fetchMessageInfos } from '../fetchers/message-fetchers';
 import {
   fetchThreadInfos,
   fetchServerThreadInfos,
   determineThreadAncestry,
 } from '../fetchers/thread-fetchers';
 import {
   checkThreadPermission,
   viewerIsMember as fetchViewerIsMember,
   checkThread,
   validateCandidateMembers,
 } from '../fetchers/thread-permission-fetchers';
 import {
   verifyUserIDs,
   verifyUserOrCookieIDs,
 } from '../fetchers/user-fetchers';
 import type { Viewer } from '../session/viewer';
 import RelationshipChangeset from '../utils/relationship-changeset';
 import { updateRoles } from './role-updaters';
 import {
   changeRole,
   recalculateThreadPermissions,
   commitMembershipChangeset,
 } from './thread-permission-updaters';
 
 async function updateRole(
   viewer: Viewer,
   request: RoleChangeRequest,
 ): Promise<ChangeThreadSettingsResult> {
   if (!viewer.loggedIn) {
     throw new ServerError('not_logged_in');
   }
 
   const [memberIDs, hasPermission] = await Promise.all([
     verifyUserIDs(request.memberIDs),
     checkThreadPermission(
       viewer,
       request.threadID,
       threadPermissions.CHANGE_ROLE,
     ),
   ]);
   if (memberIDs.length === 0) {
     throw new ServerError('invalid_parameters');
   }
   if (!hasPermission) {
     throw new ServerError('invalid_credentials');
   }
 
   const query = SQL`
     SELECT user, role
     FROM memberships
     WHERE user IN (${memberIDs}) AND thread = ${request.threadID}
   `;
   const [result] = await dbQuery(query);
 
   let nonMemberUser = false;
   let numResults = 0;
   for (const row of result) {
     if (row.role <= 0) {
       nonMemberUser = true;
       break;
     }
     numResults++;
   }
   if (nonMemberUser || numResults < memberIDs.length) {
     throw new ServerError('invalid_parameters');
   }
 
   const changeset = await changeRole(request.threadID, memberIDs, request.role);
   const { threadInfos, viewerUpdates } = await commitMembershipChangeset(
     viewer,
     changeset,
   );
 
   const messageData = {
     type: messageTypes.CHANGE_ROLE,
     threadID: request.threadID,
     creatorID: viewer.userID,
     time: Date.now(),
     userIDs: memberIDs,
     newRole: request.role,
   };
   const newMessageInfos = await createMessages(viewer, [messageData]);
 
   if (hasMinCodeVersion(viewer.platformDetails, 62)) {
     return { updatesResult: { newUpdates: viewerUpdates }, newMessageInfos };
   }
 
   return {
     threadInfo: threadInfos[request.threadID],
     threadInfos,
     updatesResult: {
       newUpdates: viewerUpdates,
     },
     newMessageInfos,
   };
 }
 
 async function removeMembers(
   viewer: Viewer,
   request: RemoveMembersRequest,
 ): Promise<ChangeThreadSettingsResult> {
   const viewerID = viewer.userID;
   if (request.memberIDs.includes(viewerID)) {
     throw new ServerError('invalid_parameters');
   }
 
   const [memberIDs, hasPermission] = await Promise.all([
     verifyUserOrCookieIDs(request.memberIDs),
     checkThreadPermission(
       viewer,
       request.threadID,
       threadPermissions.REMOVE_MEMBERS,
     ),
   ]);
   if (memberIDs.length === 0) {
     throw new ServerError('invalid_parameters');
   }
   if (!hasPermission) {
     throw new ServerError('invalid_credentials');
   }
 
   const query = SQL`
     SELECT m.user, m.role, t.default_role
     FROM memberships m
     LEFT JOIN threads t ON t.id = m.thread
     WHERE m.user IN (${memberIDs}) AND m.thread = ${request.threadID}
   `;
   const [result] = await dbQuery(query);
 
   let nonDefaultRoleUser = false;
   const actualMemberIDs = [];
   for (const row of result) {
     if (row.role <= 0) {
       continue;
     }
     actualMemberIDs.push(row.user.toString());
     if (row.role !== row.default_role) {
       nonDefaultRoleUser = true;
     }
   }
 
   if (nonDefaultRoleUser) {
     const hasChangeRolePermission = await checkThreadPermission(
       viewer,
       request.threadID,
       threadPermissions.CHANGE_ROLE,
     );
     if (!hasChangeRolePermission) {
       throw new ServerError('invalid_credentials');
     }
   }
 
   const changeset = await changeRole(request.threadID, actualMemberIDs, 0);
   const { threadInfos, viewerUpdates } = await commitMembershipChangeset(
     viewer,
     changeset,
   );
 
   const newMessageInfos = await (async () => {
     if (actualMemberIDs.length === 0) {
       return [];
     }
     const messageData = {
       type: messageTypes.REMOVE_MEMBERS,
       threadID: request.threadID,
       creatorID: viewerID,
       time: Date.now(),
       removedUserIDs: actualMemberIDs,
     };
     return await createMessages(viewer, [messageData]);
   })();
 
   if (hasMinCodeVersion(viewer.platformDetails, 62)) {
     return { updatesResult: { newUpdates: viewerUpdates }, newMessageInfos };
   }
 
   return {
     threadInfo: threadInfos[request.threadID],
     threadInfos,
     updatesResult: {
       newUpdates: viewerUpdates,
     },
     newMessageInfos,
   };
 }
 
 async function leaveThread(
   viewer: Viewer,
   request: LeaveThreadRequest,
 ): Promise<LeaveThreadResult> {
   if (!viewer.loggedIn) {
     throw new ServerError('not_logged_in');
   }
 
   const [fetchThreadResult, hasPermission] = await Promise.all([
     fetchThreadInfos(viewer, SQL`t.id = ${request.threadID}`),
     checkThreadPermission(
       viewer,
       request.threadID,
       threadPermissions.LEAVE_THREAD,
     ),
   ]);
 
   const threadInfo = fetchThreadResult.threadInfos[request.threadID];
 
   if (!viewerIsMember(threadInfo)) {
     if (hasMinCodeVersion(viewer.platformDetails, 62)) {
       return {
         updatesResult: { newUpdates: [] },
       };
     }
     const { threadInfos } = await fetchThreadInfos(viewer);
     return {
       threadInfos,
       updatesResult: {
         newUpdates: [],
       },
     };
   }
 
   if (!hasPermission) {
     throw new ServerError('invalid_parameters');
   }
 
   const viewerID = viewer.userID;
   if (threadHasAdminRole(threadInfo)) {
     let otherUsersExist = false;
     let otherAdminsExist = false;
     for (const member of threadInfo.members) {
       const role = member.role;
       if (!role || member.id === viewerID) {
         continue;
       }
       otherUsersExist = true;
       if (roleIsAdminRole(threadInfo.roles[role])) {
         otherAdminsExist = true;
         break;
       }
     }
     if (otherUsersExist && !otherAdminsExist) {
       throw new ServerError('invalid_parameters');
     }
   }
 
   const changeset = await changeRole(request.threadID, [viewerID], 0);
   const { threadInfos, viewerUpdates } = await commitMembershipChangeset(
     viewer,
     changeset,
   );
 
   const messageData = {
     type: messageTypes.LEAVE_THREAD,
     threadID: request.threadID,
     creatorID: viewerID,
     time: Date.now(),
   };
   await createMessages(viewer, [messageData]);
 
   if (hasMinCodeVersion(viewer.platformDetails, 62)) {
     return { updatesResult: { newUpdates: viewerUpdates } };
   }
 
   return {
     threadInfos,
     updatesResult: {
       newUpdates: viewerUpdates,
     },
   };
 }
 
 type UpdateThreadOptions = Shape<{
   +forceAddMembers: boolean,
   +forceUpdateRoot: boolean,
   +silenceMessages: boolean,
   +ignorePermissions: boolean,
 }>;
 
 async function updateThread(
   viewer: Viewer,
   request: UpdateThreadRequest,
   options?: UpdateThreadOptions,
 ): Promise<ChangeThreadSettingsResult> {
   if (!viewer.loggedIn) {
     throw new ServerError('not_logged_in');
   }
   const forceAddMembers = options?.forceAddMembers ?? false;
   const forceUpdateRoot = options?.forceUpdateRoot ?? false;
   const silenceMessages = options?.silenceMessages ?? false;
   const ignorePermissions =
     (options?.ignorePermissions && viewer.isScriptViewer) ?? false;
   const validationPromises = {};
 
   const changedFields = {};
   const sqlUpdate = {};
   const untrimmedName = request.changes.name;
   if (untrimmedName !== undefined && untrimmedName !== null) {
     const name = firstLine(untrimmedName);
     changedFields.name = name;
     sqlUpdate.name = name ?? null;
   }
   const { description } = request.changes;
   if (description !== undefined && description !== null) {
     changedFields.description = description;
     sqlUpdate.description = description ?? null;
   }
   if (request.changes.color) {
     const color = request.changes.color.toLowerCase();
     changedFields.color = color;
     sqlUpdate.color = color;
   }
   const { parentThreadID } = request.changes;
   if (parentThreadID !== undefined) {
     // TODO some sort of message when this changes
     sqlUpdate.parent_thread_id = parentThreadID;
   }
 
   const threadType = request.changes.type;
   if (threadType !== null && threadType !== undefined) {
     changedFields.type = threadType;
     sqlUpdate.type = threadType;
   }
 
   if (
     !ignorePermissions &&
     threadType !== null &&
     threadType !== undefined &&
     threadType !== threadTypes.COMMUNITY_OPEN_SUBTHREAD &&
     threadType !== threadTypes.COMMUNITY_SECRET_SUBTHREAD
   ) {
     throw new ServerError('invalid_parameters');
   }
 
   const newMemberIDs =
     request.changes.newMemberIDs && request.changes.newMemberIDs.length > 0
       ? [...new Set(request.changes.newMemberIDs)]
       : null;
 
   if (
     Object.keys(sqlUpdate).length === 0 &&
     !newMemberIDs &&
     !forceUpdateRoot
   ) {
     throw new ServerError('invalid_parameters');
   }
 
   validationPromises.serverThreadInfos = fetchServerThreadInfos(
     SQL`t.id = ${request.threadID}`,
   );
 
   validationPromises.hasNecessaryPermissions = (async () => {
     if (ignorePermissions) {
       return;
     }
     const checks = [];
     if (sqlUpdate.name !== undefined) {
       checks.push({
         check: 'permission',
         permission: threadPermissions.EDIT_THREAD_NAME,
       });
     }
     if (sqlUpdate.description !== undefined) {
       checks.push({
         check: 'permission',
         permission: threadPermissions.EDIT_THREAD_DESCRIPTION,
       });
     }
     if (sqlUpdate.color !== undefined) {
       checks.push({
         check: 'permission',
         permission: threadPermissions.EDIT_THREAD_COLOR,
       });
     }
     if (parentThreadID !== undefined || sqlUpdate.type !== undefined) {
       checks.push({
         check: 'permission',
         permission: threadPermissions.EDIT_PERMISSIONS,
       });
     }
     if (newMemberIDs) {
       checks.push({
         check: 'permission',
         permission: threadPermissions.ADD_MEMBERS,
       });
     }
     const hasNecessaryPermissions = await checkThread(
       viewer,
       request.threadID,
       checks,
     );
     if (!hasNecessaryPermissions) {
       throw new ServerError('invalid_credentials');
     }
   })();
 
   const { serverThreadInfos } = await promiseAll(validationPromises);
 
   const serverThreadInfo = serverThreadInfos.threadInfos[request.threadID];
   if (!serverThreadInfo) {
     throw new ServerError('internal_error');
   }
 
   // Threads with source message should be visible to everyone, but we can't
   // guarantee it for COMMUNITY_SECRET_SUBTHREAD threads so we forbid it for
   // now. In the future, if we want to support this, we would need to unlink the
   // source message.
   if (
     threadType !== null &&
     threadType !== undefined &&
     threadType !== threadTypes.SIDEBAR &&
     threadType !== threadTypes.COMMUNITY_OPEN_SUBTHREAD &&
     serverThreadInfo.sourceMessageID
   ) {
     throw new ServerError('invalid_parameters');
   }
 
   // You can't change the parent thread of a current or former SIDEBAR
   if (parentThreadID !== undefined && serverThreadInfo.sourceMessageID) {
     throw new ServerError('invalid_parameters');
   }
 
   const oldThreadType = serverThreadInfo.type;
   const oldParentThreadID = serverThreadInfo.parentThreadID;
   const oldContainingThreadID = serverThreadInfo.containingThreadID;
   const oldCommunity = serverThreadInfo.community;
   const oldDepth = serverThreadInfo.depth;
 
   const nextThreadType =
     threadType !== null && threadType !== undefined
       ? threadType
       : oldThreadType;
   let nextParentThreadID =
     parentThreadID !== undefined ? parentThreadID : oldParentThreadID;
 
   // Does the new thread type preclude a parent?
   if (
     threadType !== undefined &&
     threadType !== null &&
     getThreadTypeParentRequirement(threadType) === 'disabled' &&
     nextParentThreadID !== null
   ) {
     nextParentThreadID = null;
     sqlUpdate.parent_thread_id = null;
   }
 
   // Does the new thread type require a parent?
   if (
     threadType !== undefined &&
     threadType !== null &&
     getThreadTypeParentRequirement(threadType) === 'required' &&
     nextParentThreadID === null
   ) {
     throw new ServerError('no_parent_thread_specified');
   }
 
   const determineThreadAncestryPromise = determineThreadAncestry(
     nextParentThreadID,
     nextThreadType,
   );
 
   const confirmParentPermissionPromise = (async () => {
     if (ignorePermissions || !nextParentThreadID) {
       return;
     }
     if (
       nextParentThreadID === oldParentThreadID &&
       (nextThreadType === threadTypes.SIDEBAR) ===
         (oldThreadType === threadTypes.SIDEBAR)
     ) {
       return;
     }
     const hasParentPermission = await checkThreadPermission(
       viewer,
       nextParentThreadID,
       nextThreadType === threadTypes.SIDEBAR
         ? threadPermissions.CREATE_SIDEBARS
         : threadPermissions.CREATE_SUBCHANNELS,
     );
     if (!hasParentPermission) {
       throw new ServerError('invalid_parameters');
     }
   })();
 
   const rolesNeedUpdate = forceUpdateRoot || nextThreadType !== oldThreadType;
 
   const validateNewMembersPromise = (async () => {
     if (!newMemberIDs || ignorePermissions) {
       return;
     }
 
     const defaultRolePermissionsPromise = (async () => {
       let rolePermissions;
       if (!rolesNeedUpdate) {
         const rolePermissionsQuery = SQL`
           SELECT r.permissions
           FROM threads t
           LEFT JOIN roles r ON r.id = t.default_role
           WHERE t.id = ${request.threadID}
         `;
         const [result] = await dbQuery(rolePermissionsQuery);
         if (result.length > 0) {
           rolePermissions = result[0].permissions;
         }
       }
       if (!rolePermissions) {
         rolePermissions = getRolePermissionBlobs(nextThreadType).Members;
       }
       return rolePermissions;
     })();
 
     const [defaultRolePermissions, nextThreadAncestry] = await Promise.all([
       defaultRolePermissionsPromise,
       determineThreadAncestryPromise,
     ]);
 
     const { newMemberIDs: validatedIDs } = await validateCandidateMembers(
       viewer,
       { newMemberIDs },
       {
         threadType: nextThreadType,
         parentThreadID: nextParentThreadID,
         containingThreadID: nextThreadAncestry.containingThreadID,
         defaultRolePermissions,
       },
       { requireRelationship: !forceAddMembers },
     );
     if (
       validatedIDs &&
       Number(validatedIDs?.length) < Number(newMemberIDs?.length)
     ) {
       throw new ServerError('invalid_credentials');
     }
   })();
 
   const { nextThreadAncestry } = await promiseAll({
     nextThreadAncestry: determineThreadAncestryPromise,
     confirmParentPermissionPromise,
     validateNewMembersPromise,
   });
   if (nextThreadAncestry.containingThreadID !== oldContainingThreadID) {
     sqlUpdate.containing_thread_id = nextThreadAncestry.containingThreadID;
   }
   if (nextThreadAncestry.community !== oldCommunity) {
     if (!ignorePermissions) {
       throw new ServerError('invalid_parameters');
     }
     sqlUpdate.community = nextThreadAncestry.community;
   }
   if (nextThreadAncestry.depth !== oldDepth) {
     sqlUpdate.depth = nextThreadAncestry.depth;
   }
 
   const updateQueryPromise = (async () => {
     if (Object.keys(sqlUpdate).length === 0) {
       return;
     }
     const updateQuery = SQL`
       UPDATE threads SET ${sqlUpdate} WHERE id = ${request.threadID}
     `;
     await dbQuery(updateQuery);
   })();
 
   const updateRolesPromise = (async () => {
     if (rolesNeedUpdate) {
       await updateRoles(viewer, request.threadID, nextThreadType);
     }
   })();
 
   const intermediatePromises = {};
   intermediatePromises.updateQuery = updateQueryPromise;
   intermediatePromises.updateRoles = updateRolesPromise;
 
   if (newMemberIDs) {
     intermediatePromises.addMembersChangeset = (async () => {
       await Promise.all([updateQueryPromise, updateRolesPromise]);
       return await changeRole(request.threadID, newMemberIDs, null, {
         setNewMembersToUnread: true,
       });
     })();
   }
 
   const threadRootChanged =
     rolesNeedUpdate || nextParentThreadID !== oldParentThreadID;
   if (threadRootChanged) {
     intermediatePromises.recalculatePermissionsChangeset = (async () => {
       await Promise.all([updateQueryPromise, updateRolesPromise]);
       return await recalculateThreadPermissions(request.threadID);
     })();
   }
 
   const {
     addMembersChangeset,
     recalculatePermissionsChangeset,
   } = await promiseAll(intermediatePromises);
 
   const membershipRows = [];
   const relationshipChangeset = new RelationshipChangeset();
   if (recalculatePermissionsChangeset) {
     const {
       membershipRows: recalculateMembershipRows,
       relationshipChangeset: recalculateRelationshipChangeset,
     } = recalculatePermissionsChangeset;
     membershipRows.push(...recalculateMembershipRows);
     relationshipChangeset.addAll(recalculateRelationshipChangeset);
   }
   let addedMemberIDs;
   if (addMembersChangeset) {
     const {
       membershipRows: addMembersMembershipRows,
       relationshipChangeset: addMembersRelationshipChangeset,
     } = addMembersChangeset;
     addedMemberIDs = addMembersMembershipRows
       .filter(row => row.operation === 'save' && Number(row.role) > 0)
       .map(row => row.userID);
     membershipRows.push(...addMembersMembershipRows);
     relationshipChangeset.addAll(addMembersRelationshipChangeset);
   }
 
   const changeset = { membershipRows, relationshipChangeset };
   const { threadInfos, viewerUpdates } = await commitMembershipChangeset(
     viewer,
     changeset,
     {
       // This forces an update for this thread,
       // regardless of whether any membership rows are changed
       changedThreadIDs:
         Object.keys(sqlUpdate).length > 0
           ? new Set([request.threadID])
           : new Set(),
     },
   );
 
   let newMessageInfos = [];
   if (!silenceMessages) {
     const time = Date.now();
     const messageDatas = [];
     for (const fieldName in changedFields) {
       const newValue = changedFields[fieldName];
       messageDatas.push({
         type: messageTypes.CHANGE_SETTINGS,
         threadID: request.threadID,
         creatorID: viewer.userID,
         time,
         field: fieldName,
         value: newValue,
       });
     }
     if (addedMemberIDs && addedMemberIDs.length > 0) {
       messageDatas.push({
         type: messageTypes.ADD_MEMBERS,
         threadID: request.threadID,
         creatorID: viewer.userID,
         time,
         addedUserIDs: addedMemberIDs,
       });
     }
     newMessageInfos = await createMessages(viewer, messageDatas);
   }
 
   if (hasMinCodeVersion(viewer.platformDetails, 62)) {
     return { updatesResult: { newUpdates: viewerUpdates }, newMessageInfos };
   }
 
   return {
     threadInfo: threadInfos[request.threadID],
     threadInfos,
     updatesResult: {
       newUpdates: viewerUpdates,
     },
     newMessageInfos,
   };
 }
 
 async function joinThread(
   viewer: Viewer,
   request: ServerThreadJoinRequest,
 ): Promise<ThreadJoinResult> {
   if (!viewer.loggedIn) {
     throw new ServerError('not_logged_in');
   }
 
   const [isMember, hasPermission] = await Promise.all([
     fetchViewerIsMember(viewer, request.threadID),
     checkThreadPermission(
       viewer,
       request.threadID,
       threadPermissions.JOIN_THREAD,
     ),
   ]);
   if (!hasPermission) {
     throw new ServerError('invalid_parameters');
   }
 
   // TODO: determine code version
   const hasCodeVersionBelow87 = !hasMinCodeVersion(viewer.platformDetails, 87);
   const hasCodeVersionBelow62 = !hasMinCodeVersion(viewer.platformDetails, 62);
 
   const { calendarQuery } = request;
   if (isMember) {
     const response: ThreadJoinResult = {
       rawMessageInfos: [],
       truncationStatuses: {},
       userInfos: {},
       updatesResult: {
         newUpdates: [],
       },
     };
     if (calendarQuery && hasCodeVersionBelow87) {
       response.rawEntryInfos = [];
     }
     if (hasCodeVersionBelow62) {
       response.threadInfos = {};
     }
     return response;
   }
 
   if (calendarQuery) {
     const threadFilterIDs = filteredThreadIDs(calendarQuery.filters);
     if (
       !threadFilterIDs ||
       threadFilterIDs.size !== 1 ||
       threadFilterIDs.values().next().value !== request.threadID
     ) {
       throw new ServerError('invalid_parameters');
     }
   }
 
   const changeset = await changeRole(request.threadID, [viewer.userID], null);
 
   const membershipResult = await commitMembershipChangeset(viewer, changeset, {
     calendarQuery,
   });
 
   const messageData = {
     type: messageTypes.JOIN_THREAD,
     threadID: request.threadID,
     creatorID: viewer.userID,
     time: Date.now(),
   };
   const newMessages = await createMessages(viewer, [messageData]);
 
-  const threadSelectionCriteria = {
+  const messageSelectionCriteria = {
     threadCursors: { [request.threadID]: false },
   };
 
   if (!hasCodeVersionBelow87) {
     return {
       rawMessageInfos: newMessages,
       truncationStatuses: {},
       userInfos: membershipResult.userInfos,
       updatesResult: {
         newUpdates: membershipResult.viewerUpdates,
       },
     };
   }
 
   const [fetchMessagesResult, fetchEntriesResult] = await Promise.all([
-    fetchMessageInfos(viewer, threadSelectionCriteria, defaultNumberPerThread),
+    fetchMessageInfos(viewer, messageSelectionCriteria, defaultNumberPerThread),
     calendarQuery ? fetchEntryInfos(viewer, [calendarQuery]) : undefined,
   ]);
   const rawEntryInfos = fetchEntriesResult && fetchEntriesResult.rawEntryInfos;
   const response: ThreadJoinResult = {
     rawMessageInfos: fetchMessagesResult.rawMessageInfos,
     truncationStatuses: fetchMessagesResult.truncationStatuses,
     userInfos: membershipResult.userInfos,
     updatesResult: {
       newUpdates: membershipResult.viewerUpdates,
     },
   };
   if (hasCodeVersionBelow62) {
     response.threadInfos = membershipResult.threadInfos;
   }
   if (rawEntryInfos) {
     response.rawEntryInfos = rawEntryInfos;
   }
   return response;
 }
 
 async function updateThreadMembers(viewer: Viewer) {
   const { threadInfos } = await fetchThreadInfos(
     viewer,
     SQL`t.parent_thread_id IS NOT NULL `,
   );
 
   const updateDatas = [];
   const time = Date.now();
   for (const threadID in threadInfos) {
     updateDatas.push({
       type: updateTypes.UPDATE_THREAD,
       userID: viewer.id,
       time,
       threadID: threadID,
       targetSession: viewer.session,
     });
   }
 
   await createUpdates(updateDatas);
 }
 
 export {
   updateRole,
   removeMembers,
   leaveThread,
   updateThread,
   joinThread,
   updateThreadMembers,
 };