diff --git a/keyserver/src/fetchers/thread-fetchers.js b/keyserver/src/fetchers/thread-fetchers.js
index a9ba51e0c..60ad76049 100644
--- a/keyserver/src/fetchers/thread-fetchers.js
+++ b/keyserver/src/fetchers/thread-fetchers.js
@@ -1,278 +1,284 @@
 // @flow
 
 import { getAllThreadPermissions } from 'lib/permissions/thread-permissions.js';
 import {
   rawThreadInfoFromServerThreadInfo,
   getContainingThreadID,
   getCommunity,
 } from 'lib/shared/thread-utils.js';
 import { hasMinCodeVersion } from 'lib/shared/version-utils.js';
 import type { RawMessageInfo, MessageInfo } from 'lib/types/message-types.js';
 import {
   threadTypes,
   type ThreadType,
   type RawThreadInfo,
   type ServerThreadInfo,
 } from 'lib/types/thread-types.js';
 import { ServerError } from 'lib/utils/errors.js';
 
 import { dbQuery, SQL } from '../database/database.js';
 import type { SQLStatementType } from '../database/types.js';
 import type { Viewer } from '../session/viewer.js';
 
 type FetchServerThreadInfosResult = {
   +threadInfos: { +[id: string]: ServerThreadInfo },
 };
 
 async function fetchServerThreadInfos(
   condition?: SQLStatementType,
 ): Promise<FetchServerThreadInfosResult> {
   const whereClause = condition ? SQL`WHERE `.append(condition) : '';
 
   const rolesQuery = SQL`
     SELECT t.id, t.default_role, r.id AS role, r.name, r.permissions
     FROM threads t
     LEFT JOIN roles r ON r.thread = t.id
   `.append(whereClause);
 
   const threadsQuery = SQL`
     SELECT t.id, t.name, t.parent_thread_id, t.containing_thread_id,
       t.community, t.depth, t.color, t.description, t.type, t.creation_time,
       t.source_message, t.replies_count, t.avatar, m.user, m.role, m.permissions,
       m.subscription, m.last_read_message < m.last_message AS unread, m.sender
     FROM threads t
     LEFT JOIN memberships m ON m.thread = t.id AND m.role >= 0
   `
     .append(whereClause)
     .append(SQL` ORDER BY m.user ASC`);
   const [[threadsResult], [rolesResult]] = await Promise.all([
     dbQuery(threadsQuery),
     dbQuery(rolesQuery),
   ]);
 
   const threadInfos = {};
   for (const threadsRow of threadsResult) {
     const threadID = threadsRow.id.toString();
     if (!threadInfos[threadID]) {
       threadInfos[threadID] = {
         id: threadID,
         type: threadsRow.type,
         name: threadsRow.name ? threadsRow.name : '',
         description: threadsRow.description ? threadsRow.description : '',
         color: threadsRow.color,
         creationTime: threadsRow.creation_time,
         parentThreadID: threadsRow.parent_thread_id
           ? threadsRow.parent_thread_id.toString()
           : null,
         containingThreadID: threadsRow.containing_thread_id
           ? threadsRow.containing_thread_id.toString()
           : null,
         depth: threadsRow.depth,
         community: threadsRow.community
           ? threadsRow.community.toString()
           : null,
         members: [],
         roles: {},
         repliesCount: threadsRow.replies_count,
       };
       if (threadsRow.avatar) {
         threadInfos[threadID] = {
           ...threadInfos[threadID],
           avatar: JSON.parse(threadsRow.avatar),
         };
       }
     }
     const sourceMessageID = threadsRow.source_message?.toString();
     if (sourceMessageID) {
       threadInfos[threadID].sourceMessageID = sourceMessageID;
     }
     if (threadsRow.user) {
       const userID = threadsRow.user.toString();
       const allPermissions = getAllThreadPermissions(
         JSON.parse(threadsRow.permissions),
         threadID,
       );
       threadInfos[threadID].members.push({
         id: userID,
         permissions: allPermissions,
         role: threadsRow.role ? threadsRow.role.toString() : null,
         subscription: JSON.parse(threadsRow.subscription),
         unread: threadsRow.role ? !!threadsRow.unread : null,
         isSender: !!threadsRow.sender,
       });
     }
   }
 
   for (const rolesRow of rolesResult) {
     const threadID = rolesRow.id.toString();
     if (!rolesRow.role) {
       continue;
     }
     const role = rolesRow.role.toString();
     if (!threadInfos[threadID].roles[role]) {
       threadInfos[threadID].roles[role] = {
         id: role,
         name: rolesRow.name,
         permissions: JSON.parse(rolesRow.permissions),
         isDefault: role === rolesRow.default_role.toString(),
       };
     }
   }
 
   return { threadInfos };
 }
 
 export type FetchThreadInfosResult = {
   +threadInfos: { +[id: string]: RawThreadInfo },
 };
 
 async function fetchThreadInfos(
   viewer: Viewer,
   condition?: SQLStatementType,
 ): Promise<FetchThreadInfosResult> {
   const serverResult = await fetchServerThreadInfos(condition);
   return rawThreadInfosFromServerThreadInfos(viewer, serverResult);
 }
 
 const shimCommunityRoot = {
   [threadTypes.COMMUNITY_ROOT]: threadTypes.COMMUNITY_SECRET_SUBTHREAD,
   [threadTypes.COMMUNITY_ANNOUNCEMENT_ROOT]:
     threadTypes.COMMUNITY_SECRET_SUBTHREAD,
   [threadTypes.COMMUNITY_OPEN_ANNOUNCEMENT_SUBTHREAD]:
     threadTypes.COMMUNITY_OPEN_SUBTHREAD,
   [threadTypes.COMMUNITY_SECRET_ANNOUNCEMENT_SUBTHREAD]:
     threadTypes.COMMUNITY_SECRET_SUBTHREAD,
   [threadTypes.GENESIS]: threadTypes.COMMUNITY_SECRET_SUBTHREAD,
 };
 
 function rawThreadInfosFromServerThreadInfos(
   viewer: Viewer,
   serverResult: FetchServerThreadInfosResult,
 ): FetchThreadInfosResult {
   const viewerID = viewer.id;
   const hasCodeVersionBelow70 = !hasMinCodeVersion(viewer.platformDetails, 70);
   const hasCodeVersionBelow87 = !hasMinCodeVersion(viewer.platformDetails, 87);
   const hasCodeVersionBelow102 = !hasMinCodeVersion(
     viewer.platformDetails,
     102,
   );
   const hasCodeVersionBelow104 = !hasMinCodeVersion(
     viewer.platformDetails,
     104,
   );
+
+  // TODO (atul): Replace with `hasMinCodeVersion` check once we have a
+  //              native release with thread avatar editing enabled.
+  const filterThreadEditAvatarPermission = true;
+
   const threadInfos = {};
   for (const threadID in serverResult.threadInfos) {
     const serverThreadInfo = serverResult.threadInfos[threadID];
     const threadInfo = rawThreadInfoFromServerThreadInfo(
       serverThreadInfo,
       viewerID,
       {
         includeVisibilityRules: hasCodeVersionBelow70,
         filterMemberList: hasCodeVersionBelow70,
         shimThreadTypes: hasCodeVersionBelow87 ? shimCommunityRoot : null,
         hideThreadStructure: hasCodeVersionBelow102,
         filterDetailedThreadEditPermissions: hasCodeVersionBelow104,
+        filterThreadEditAvatarPermission,
       },
     );
     if (threadInfo) {
       threadInfos[threadID] = threadInfo;
     }
   }
   return { threadInfos };
 }
 
 async function verifyThreadIDs(
   threadIDs: $ReadOnlyArray<string>,
 ): Promise<$ReadOnlyArray<string>> {
   if (threadIDs.length === 0) {
     return [];
   }
 
   const query = SQL`SELECT id FROM threads WHERE id IN (${threadIDs})`;
   const [result] = await dbQuery(query);
 
   const verified = [];
   for (const row of result) {
     verified.push(row.id.toString());
   }
   return verified;
 }
 
 async function verifyThreadID(threadID: string): Promise<boolean> {
   const result = await verifyThreadIDs([threadID]);
   return result.length !== 0;
 }
 
 type ThreadAncestry = {
   +containingThreadID: ?string,
   +community: ?string,
   +depth: number,
 };
 async function determineThreadAncestry(
   parentThreadID: ?string,
   threadType: ThreadType,
 ): Promise<ThreadAncestry> {
   if (!parentThreadID) {
     return { containingThreadID: null, community: null, depth: 0 };
   }
   const parentThreadInfos = await fetchServerThreadInfos(
     SQL`t.id = ${parentThreadID}`,
   );
   const parentThreadInfo = parentThreadInfos.threadInfos[parentThreadID];
   if (!parentThreadInfo) {
     throw new ServerError('invalid_parameters');
   }
   const containingThreadID = getContainingThreadID(
     parentThreadInfo,
     threadType,
   );
   const community = getCommunity(parentThreadInfo);
   const depth = parentThreadInfo.depth + 1;
   return { containingThreadID, community, depth };
 }
 
 function personalThreadQuery(
   firstMemberID: string,
   secondMemberID: string,
 ): SQLStatementType {
   return SQL`
     SELECT t.id 
     FROM threads t
     INNER JOIN memberships m1 
       ON m1.thread = t.id AND m1.user = ${firstMemberID}
     INNER JOIN memberships m2
       ON m2.thread = t.id AND m2.user = ${secondMemberID}
     WHERE t.type = ${threadTypes.PERSONAL}
       AND m1.role > 0
       AND m2.role > 0
   `;
 }
 
 async function fetchPersonalThreadID(
   viewerID: string,
   otherMemberID: string,
 ): Promise<?string> {
   const query = personalThreadQuery(viewerID, otherMemberID);
   const [threads] = await dbQuery(query);
   return threads[0]?.id.toString();
 }
 
 async function serverThreadInfoFromMessageInfo(
   message: RawMessageInfo | MessageInfo,
 ): Promise<?ServerThreadInfo> {
   const threadID = message.threadID;
   const threads = await fetchServerThreadInfos(SQL`t.id = ${threadID}`);
   return threads.threadInfos[threadID];
 }
 
 export {
   fetchServerThreadInfos,
   fetchThreadInfos,
   rawThreadInfosFromServerThreadInfos,
   verifyThreadIDs,
   verifyThreadID,
   determineThreadAncestry,
   personalThreadQuery,
   fetchPersonalThreadID,
   serverThreadInfoFromMessageInfo,
 };
diff --git a/lib/shared/thread-utils.js b/lib/shared/thread-utils.js
index 98d3b6e77..3a2c53204 100644
--- a/lib/shared/thread-utils.js
+++ b/lib/shared/thread-utils.js
@@ -1,1610 +1,1620 @@
 // @flow
 
 import invariant from 'invariant';
 import _find from 'lodash/fp/find.js';
 import _mapValues from 'lodash/fp/mapValues.js';
 import _omitBy from 'lodash/fp/omitBy.js';
 import * as React from 'react';
 
 import { generatePendingThreadColor } from './color-utils.js';
 import { type ParserRules } from './markdown.js';
 import { extractMentionsFromText } from './mention-utils.js';
 import { getMessageTitle } from './message-utils.js';
 import { relationshipBlockedInEitherDirection } from './relationship-utils.js';
 import threadWatcher from './thread-watcher.js';
 import {
   fetchMostRecentMessagesActionTypes,
   fetchMostRecentMessages,
 } from '../actions/message-actions.js';
 import {
   changeThreadMemberRolesActionTypes,
   newThreadActionTypes,
   removeUsersFromThreadActionTypes,
 } from '../actions/thread-actions.js';
 import { searchUsers as searchUserCall } from '../actions/user-actions.js';
 import ashoat from '../facts/ashoat.js';
 import genesis from '../facts/genesis.js';
 import { useLoggedInUserInfo } from '../hooks/account-hooks.js';
 import {
   permissionLookup,
   getAllThreadPermissions,
   makePermissionsBlob,
 } from '../permissions/thread-permissions.js';
 import type {
   ChatThreadItem,
   ChatMessageInfoItem,
 } from '../selectors/chat-selectors.js';
 import { useGlobalThreadSearchIndex } from '../selectors/nav-selectors.js';
 import {
   threadInfoSelector,
   pendingToRealizedThreadIDsSelector,
 } from '../selectors/thread-selectors.js';
 import {
   getRelativeMemberInfos,
   usersWithPersonalThreadSelector,
 } from '../selectors/user-selectors.js';
 import { getUserAvatarForThread } from '../shared/avatar-utils.js';
 import type { CalendarQuery } from '../types/entry-types.js';
 import {
   type RobotextMessageInfo,
   type ComposableMessageInfo,
   messageTypes,
 } from '../types/message-types.js';
 import { userRelationshipStatus } from '../types/relationship-types.js';
 import {
   type RawThreadInfo,
   type ThreadInfo,
   type ThreadPermission,
   type MemberInfo,
   type ServerThreadInfo,
   type RelativeMemberInfo,
   type ThreadCurrentUserInfo,
   type RoleInfo,
   type ServerMemberInfo,
   type ThreadPermissionsInfo,
   type ThreadType,
   type ClientNewThreadRequest,
   type NewThreadResult,
   type ChangeThreadSettingsPayload,
   threadTypes,
   threadPermissions,
   threadTypeIsCommunityRoot,
   assertThreadType,
+  threadPermissionPropagationPrefixes,
 } from '../types/thread-types.js';
 import { type ClientUpdateInfo, updateTypes } from '../types/update-types.js';
 import type {
   GlobalAccountUserInfo,
   UserInfos,
   AccountUserInfo,
   LoggedInUserInfo,
 } from '../types/user-types.js';
 import {
   useDispatchActionPromise,
   useServerCall,
 } from '../utils/action-utils.js';
 import type { DispatchActionPromise } from '../utils/action-utils.js';
 import type { GetENSNames } from '../utils/ens-helpers.js';
 import {
   ET,
   entityTextToRawString,
   getEntityTextAsString,
   type ThreadEntity,
 } from '../utils/entity-text.js';
 import { useSelector } from '../utils/redux-utils.js';
 import { firstLine } from '../utils/string-utils.js';
 import { trimText } from '../utils/text-utils.js';
 
 const chatNameMaxLength = 191;
 const chatNameMinLength = 0;
 const secondCharRange = `{${chatNameMinLength},${chatNameMaxLength}}`;
 const validChatNameRegexString = `^.${secondCharRange}$`;
 const validChatNameRegex: RegExp = new RegExp(validChatNameRegexString);
 
 function threadHasPermission(
   threadInfo: ?(ThreadInfo | RawThreadInfo),
   permission: ThreadPermission,
 ): boolean {
   if (!threadInfo) {
     return false;
   }
   invariant(
     !permissionsDisabledByBlock.has(permission) || threadInfo?.uiName,
     `${permission} can be disabled by a block, but threadHasPermission can't ` +
       'check for a block on RawThreadInfo. Please pass in ThreadInfo instead!',
   );
   if (!threadInfo.currentUser.permissions[permission]) {
     return false;
   }
   return threadInfo.currentUser.permissions[permission].value;
 }
 
 function viewerIsMember(threadInfo: ?(ThreadInfo | RawThreadInfo)): boolean {
   return !!(
     threadInfo &&
     threadInfo.currentUser.role !== null &&
     threadInfo.currentUser.role !== undefined
   );
 }
 
 function threadIsInHome(threadInfo: ?(ThreadInfo | RawThreadInfo)): boolean {
   return !!(threadInfo && threadInfo.currentUser.subscription.home);
 }
 
 // Can have messages
 function threadInChatList(threadInfo: ?(ThreadInfo | RawThreadInfo)): boolean {
   return (
     viewerIsMember(threadInfo) &&
     threadHasPermission(threadInfo, threadPermissions.VISIBLE)
   );
 }
 
 function threadIsTopLevel(threadInfo: ?(ThreadInfo | RawThreadInfo)): boolean {
   return threadInChatList(threadInfo) && threadIsChannel(threadInfo);
 }
 
 function threadIsChannel(threadInfo: ?(ThreadInfo | RawThreadInfo)): boolean {
   return !!(threadInfo && threadInfo.type !== threadTypes.SIDEBAR);
 }
 
 function threadIsSidebar(threadInfo: ?(ThreadInfo | RawThreadInfo)): boolean {
   return threadInfo?.type === threadTypes.SIDEBAR;
 }
 
 function threadInBackgroundChatList(
   threadInfo: ?(ThreadInfo | RawThreadInfo),
 ): boolean {
   return threadInChatList(threadInfo) && !threadIsInHome(threadInfo);
 }
 
 function threadInHomeChatList(
   threadInfo: ?(ThreadInfo | RawThreadInfo),
 ): boolean {
   return threadInChatList(threadInfo) && threadIsInHome(threadInfo);
 }
 
 // Can have Calendar entries,
 // does appear as a top-level entity in the thread list
 function threadInFilterList(
   threadInfo: ?(ThreadInfo | RawThreadInfo),
 ): boolean {
   return (
     threadInChatList(threadInfo) &&
     !!threadInfo &&
     threadInfo.type !== threadTypes.SIDEBAR
   );
 }
 
 function userIsMember(
   threadInfo: ?(ThreadInfo | RawThreadInfo),
   userID: string,
 ): boolean {
   if (!threadInfo) {
     return false;
   }
   if (threadInfo.id === genesis.id) {
     return true;
   }
   return threadInfo.members.some(member => member.id === userID && member.role);
 }
 
 function threadActualMembers(
   memberInfos: $ReadOnlyArray<MemberInfo | RelativeMemberInfo>,
 ): $ReadOnlyArray<string> {
   return memberInfos
     .filter(memberInfo => memberInfo.role)
     .map(memberInfo => memberInfo.id);
 }
 
 function threadOtherMembers<T: MemberInfo | RelativeMemberInfo>(
   memberInfos: $ReadOnlyArray<T>,
   viewerID: ?string,
 ): $ReadOnlyArray<T> {
   return memberInfos.filter(
     memberInfo => memberInfo.role && memberInfo.id !== viewerID,
   );
 }
 
 function threadMembersWithoutAddedAshoat<T: ThreadInfo | RawThreadInfo>(
   threadInfo: T,
 ): $PropertyType<T, 'members'> {
   if (threadInfo.community !== genesis.id) {
     return threadInfo.members;
   }
   return threadInfo.members.filter(
     member => member.id !== ashoat.id || member.role,
   );
 }
 
 function threadIsGroupChat(threadInfo: ThreadInfo | RawThreadInfo): boolean {
   return (
     threadMembersWithoutAddedAshoat(threadInfo).filter(
       member =>
         member.role || member.permissions[threadPermissions.VOICED]?.value,
     ).length > 2
   );
 }
 
 function threadOrParentThreadIsGroupChat(
   threadInfo: RawThreadInfo | ThreadInfo,
 ) {
   return threadMembersWithoutAddedAshoat(threadInfo).length > 2;
 }
 
 function threadIsPending(threadID: ?string): boolean {
   return !!threadID?.startsWith('pending');
 }
 
 function threadIsPendingSidebar(threadID: ?string): boolean {
   return !!threadID?.startsWith('pending/sidebar/');
 }
 
 function getSingleOtherUser(
   threadInfo: ThreadInfo | RawThreadInfo,
   viewerID: ?string,
 ): ?string {
   if (!viewerID) {
     return undefined;
   }
   const otherMembers = threadOtherMembers(threadInfo.members, viewerID);
   if (otherMembers.length !== 1) {
     return undefined;
   }
   return otherMembers[0].id;
 }
 
 function getPendingThreadID(
   threadType: ThreadType,
   memberIDs: $ReadOnlyArray<string>,
   sourceMessageID: ?string,
 ): string {
   const pendingThreadKey = sourceMessageID
     ? `sidebar/${sourceMessageID}`
     : [...memberIDs].sort().join('+');
   const pendingThreadTypeString = sourceMessageID ? '' : `type${threadType}/`;
   return `pending/${pendingThreadTypeString}${pendingThreadKey}`;
 }
 
 const pendingThreadIDRegex =
   'pending/(type[0-9]+/[0-9]+(\\+[0-9]+)*|sidebar/[0-9]+)';
 
 type PendingThreadIDContents = {
   +threadType: ThreadType,
   +memberIDs: $ReadOnlyArray<string>,
   +sourceMessageID: ?string,
 };
 
 function parsePendingThreadID(
   pendingThreadID: string,
 ): ?PendingThreadIDContents {
   const pendingRegex = new RegExp(`^${pendingThreadIDRegex}$`);
   const pendingThreadIDMatches = pendingRegex.exec(pendingThreadID);
   if (!pendingThreadIDMatches) {
     return null;
   }
   const [threadTypeString, threadKey] = pendingThreadIDMatches[1].split('/');
   const threadType =
     threadTypeString === 'sidebar'
       ? threadTypes.SIDEBAR
       : assertThreadType(Number(threadTypeString.replace('type', '')));
   const memberIDs = threadTypeString === 'sidebar' ? [] : threadKey.split('+');
   const sourceMessageID = threadTypeString === 'sidebar' ? threadKey : null;
   return {
     threadType,
     memberIDs,
     sourceMessageID,
   };
 }
 
 type UserIDAndUsername = {
   +id: string,
   +username: string,
   ...
 };
 type CreatePendingThreadArgs = {
   +viewerID: string,
   +threadType: ThreadType,
   +members: $ReadOnlyArray<UserIDAndUsername>,
   +parentThreadInfo?: ?ThreadInfo,
   +threadColor?: ?string,
   +name?: ?string,
   +sourceMessageID?: string,
 };
 
 function createPendingThread({
   viewerID,
   threadType,
   members,
   parentThreadInfo,
   threadColor,
   name,
   sourceMessageID,
 }: CreatePendingThreadArgs): ThreadInfo {
   const now = Date.now();
   if (!members.some(member => member.id === viewerID)) {
     throw new Error(
       'createPendingThread should be called with the viewer as a member',
     );
   }
 
   const memberIDs = members.map(member => member.id);
   const threadID = getPendingThreadID(threadType, memberIDs, sourceMessageID);
 
   const permissions = {
     [threadPermissions.KNOW_OF]: true,
     [threadPermissions.VISIBLE]: true,
     [threadPermissions.VOICED]: true,
   };
 
   const membershipPermissions = getAllThreadPermissions(
     makePermissionsBlob(permissions, null, threadID, threadType),
     threadID,
   );
   const role = {
     id: `${threadID}/role`,
     name: 'Members',
     permissions,
     isDefault: true,
   };
 
   const rawThreadInfo = {
     id: threadID,
     type: threadType,
     name: name ?? null,
     description: null,
     color: threadColor ?? generatePendingThreadColor(memberIDs),
     creationTime: now,
     parentThreadID: parentThreadInfo?.id ?? null,
     containingThreadID: getContainingThreadID(parentThreadInfo, threadType),
     community: getCommunity(parentThreadInfo),
     members: members.map(member => ({
       id: member.id,
       role: role.id,
       permissions: membershipPermissions,
       isSender: false,
     })),
     roles: {
       [role.id]: role,
     },
     currentUser: {
       role: role.id,
       permissions: membershipPermissions,
       subscription: {
         pushNotifs: false,
         home: false,
       },
       unread: false,
     },
     repliesCount: 0,
     sourceMessageID,
   };
 
   const userInfos = {};
   for (const member of members) {
     const { id, username } = member;
     userInfos[id] = { id, username };
   }
 
   return threadInfoFromRawThreadInfo(rawThreadInfo, viewerID, userInfos);
 }
 
 function createPendingThreadItem(
   loggedInUserInfo: LoggedInUserInfo,
   user: UserIDAndUsername,
 ): ChatThreadItem {
   const threadInfo = createPendingThread({
     viewerID: loggedInUserInfo.id,
     threadType: threadTypes.PERSONAL,
     members: [loggedInUserInfo, user],
   });
 
   return {
     type: 'chatThreadItem',
     threadInfo,
     mostRecentMessageInfo: null,
     mostRecentNonLocalMessage: null,
     lastUpdatedTime: threadInfo.creationTime,
     lastUpdatedTimeIncludingSidebars: threadInfo.creationTime,
     sidebars: [],
     pendingPersonalThreadUserInfo: {
       id: user.id,
       username: user.username,
     },
   };
 }
 
 // Returns map from lowercase username to AccountUserInfo
 function memberLowercaseUsernameMap(
   members: $ReadOnlyArray<RelativeMemberInfo>,
 ): Map<string, AccountUserInfo> {
   const memberMap = new Map();
   for (const member of members) {
     const { id, role, username } = member;
     if (!role || !username) {
       continue;
     }
     memberMap.set(username.toLowerCase(), { id, username });
   }
   return memberMap;
 }
 
 // Returns map from user ID to AccountUserInfo
 function extractMentionedMembers(
   text: string,
   threadInfo: ThreadInfo,
 ): Map<string, AccountUserInfo> {
   const memberMap = memberLowercaseUsernameMap(threadInfo.members);
   const mentions = extractMentionsFromText(text);
 
   const mentionedMembers = new Map();
   for (const mention of mentions) {
     const userInfo = memberMap.get(mention.toLowerCase());
     if (userInfo) {
       mentionedMembers.set(userInfo.id, userInfo);
     }
   }
   return mentionedMembers;
 }
 
 // When a member of the parent is mentioned in a sidebar,
 // they will be automatically added to that sidebar
 function extractNewMentionedParentMembers(
   messageText: string,
   threadInfo: ThreadInfo,
   parentThreadInfo: ThreadInfo,
 ): AccountUserInfo[] {
   const mentionedMembersOfParent = extractMentionedMembers(
     messageText,
     parentThreadInfo,
   );
   for (const member of threadInfo.members) {
     if (member.role) {
       mentionedMembersOfParent.delete(member.id);
     }
   }
   return [...mentionedMembersOfParent.values()];
 }
 
 type SharedCreatePendingSidebarInput = {
   +sourceMessageInfo: ComposableMessageInfo | RobotextMessageInfo,
   +parentThreadInfo: ThreadInfo,
   +loggedInUserInfo: LoggedInUserInfo,
 };
 
 type BaseCreatePendingSidebarInput = {
   ...SharedCreatePendingSidebarInput,
   +messageTitle: string,
 };
 function baseCreatePendingSidebar(
   input: BaseCreatePendingSidebarInput,
 ): ThreadInfo {
   const {
     sourceMessageInfo,
     parentThreadInfo,
     loggedInUserInfo,
     messageTitle,
   } = input;
   const { color, type: parentThreadType } = parentThreadInfo;
   const threadName = trimText(messageTitle, 30);
 
   const initialMembers = new Map();
 
   const { id: viewerID, username: viewerUsername } = loggedInUserInfo;
   initialMembers.set(viewerID, { id: viewerID, username: viewerUsername });
 
   if (userIsMember(parentThreadInfo, sourceMessageInfo.creator.id)) {
     const { id: sourceAuthorID, username: sourceAuthorUsername } =
       sourceMessageInfo.creator;
     invariant(
       sourceAuthorUsername,
       'sourceAuthorUsername should be set in createPendingSidebar',
     );
     const initialMemberUserInfo = {
       id: sourceAuthorID,
       username: sourceAuthorUsername,
     };
     initialMembers.set(sourceAuthorID, initialMemberUserInfo);
   }
 
   const singleOtherUser = getSingleOtherUser(parentThreadInfo, viewerID);
   if (parentThreadType === threadTypes.PERSONAL && singleOtherUser) {
     const singleOtherUsername = parentThreadInfo.members.find(
       member => member.id === singleOtherUser,
     )?.username;
     invariant(
       singleOtherUsername,
       'singleOtherUsername should be set in createPendingSidebar',
     );
     const singleOtherUserInfo = {
       id: singleOtherUser,
       username: singleOtherUsername,
     };
     initialMembers.set(singleOtherUser, singleOtherUserInfo);
   }
 
   if (sourceMessageInfo.type === messageTypes.TEXT) {
     const mentionedMembersOfParent = extractMentionedMembers(
       sourceMessageInfo.text,
       parentThreadInfo,
     );
     for (const [memberID, member] of mentionedMembersOfParent) {
       initialMembers.set(memberID, member);
     }
   }
 
   return createPendingThread({
     viewerID,
     threadType: threadTypes.SIDEBAR,
     members: [...initialMembers.values()],
     parentThreadInfo,
     threadColor: color,
     name: threadName,
     sourceMessageID: sourceMessageInfo.id,
   });
 }
 
 // The message title here may have ETH addresses that aren't resolved to ENS
 // names. This function should only be used in cases where we're sure that we
 // don't care about the thread title. We should prefer createPendingSidebar
 // wherever possible
 type CreateUnresolvedPendingSidebarInput = {
   ...SharedCreatePendingSidebarInput,
   +markdownRules: ParserRules,
 };
 function createUnresolvedPendingSidebar(
   input: CreateUnresolvedPendingSidebarInput,
 ): ThreadInfo {
   const {
     sourceMessageInfo,
     parentThreadInfo,
     loggedInUserInfo,
     markdownRules,
   } = input;
 
   const messageTitleEntityText = getMessageTitle(
     sourceMessageInfo,
     parentThreadInfo,
     markdownRules,
   );
   const messageTitle = entityTextToRawString(messageTitleEntityText, {
     ignoreViewer: true,
   });
 
   return baseCreatePendingSidebar({
     sourceMessageInfo,
     parentThreadInfo,
     messageTitle,
     loggedInUserInfo,
   });
 }
 
 type CreatePendingSidebarInput = {
   ...SharedCreatePendingSidebarInput,
   +markdownRules: ParserRules,
   +getENSNames: ?GetENSNames,
 };
 async function createPendingSidebar(
   input: CreatePendingSidebarInput,
 ): Promise<ThreadInfo> {
   const {
     sourceMessageInfo,
     parentThreadInfo,
     loggedInUserInfo,
     markdownRules,
     getENSNames,
   } = input;
 
   const messageTitleEntityText = getMessageTitle(
     sourceMessageInfo,
     parentThreadInfo,
     markdownRules,
   );
   const messageTitle = await getEntityTextAsString(
     messageTitleEntityText,
     getENSNames,
     { ignoreViewer: true },
   );
   invariant(
     messageTitle !== null && messageTitle !== undefined,
     'getEntityTextAsString only returns falsey when passed falsey',
   );
 
   return baseCreatePendingSidebar({
     sourceMessageInfo,
     parentThreadInfo,
     messageTitle,
     loggedInUserInfo,
   });
 }
 
 function pendingThreadType(numberOfOtherMembers: number): 4 | 6 | 7 {
   if (numberOfOtherMembers === 0) {
     return threadTypes.PRIVATE;
   } else if (numberOfOtherMembers === 1) {
     return threadTypes.PERSONAL;
   } else {
     return threadTypes.LOCAL;
   }
 }
 
 function threadTypeCanBePending(threadType: ThreadType): boolean {
   return (
     threadType === threadTypes.PERSONAL ||
     threadType === threadTypes.LOCAL ||
     threadType === threadTypes.SIDEBAR ||
     threadType === threadTypes.PRIVATE
   );
 }
 
 type CreateRealThreadParameters = {
   +threadInfo: ThreadInfo,
   +dispatchActionPromise: DispatchActionPromise,
   +createNewThread: ClientNewThreadRequest => Promise<NewThreadResult>,
   +sourceMessageID: ?string,
   +viewerID: ?string,
   +handleError?: () => mixed,
   +calendarQuery: CalendarQuery,
 };
 async function createRealThreadFromPendingThread({
   threadInfo,
   dispatchActionPromise,
   createNewThread,
   sourceMessageID,
   viewerID,
   calendarQuery,
 }: CreateRealThreadParameters): Promise<string> {
   if (!threadIsPending(threadInfo.id)) {
     return threadInfo.id;
   }
 
   const otherMemberIDs = threadOtherMembers(threadInfo.members, viewerID).map(
     member => member.id,
   );
   let resultPromise;
   if (threadInfo.type !== threadTypes.SIDEBAR) {
     invariant(
       otherMemberIDs.length > 0,
       'otherMemberIDs should not be empty for threads',
     );
     resultPromise = createNewThread({
       type: pendingThreadType(otherMemberIDs.length),
       initialMemberIDs: otherMemberIDs,
       color: threadInfo.color,
       calendarQuery,
     });
   } else {
     invariant(
       sourceMessageID,
       'sourceMessageID should be set when creating a sidebar',
     );
     resultPromise = createNewThread({
       type: threadTypes.SIDEBAR,
       initialMemberIDs: otherMemberIDs,
       color: threadInfo.color,
       sourceMessageID,
       parentThreadID: threadInfo.parentThreadID,
       name: threadInfo.name,
       calendarQuery,
     });
   }
   dispatchActionPromise(newThreadActionTypes, resultPromise);
   const { newThreadID } = await resultPromise;
   return newThreadID;
 }
 
 type RawThreadInfoOptions = {
   +includeVisibilityRules?: ?boolean,
   +filterMemberList?: ?boolean,
   +hideThreadStructure?: ?boolean,
   +shimThreadTypes?: ?{
     +[inType: ThreadType]: ThreadType,
   },
   +filterDetailedThreadEditPermissions?: boolean,
+  +filterThreadEditAvatarPermission?: boolean,
 };
 function rawThreadInfoFromServerThreadInfo(
   serverThreadInfo: ServerThreadInfo,
   viewerID: string,
   options?: RawThreadInfoOptions,
 ): ?RawThreadInfo {
   const includeVisibilityRules = options?.includeVisibilityRules;
   const filterMemberList = options?.filterMemberList;
   const hideThreadStructure = options?.hideThreadStructure;
   const shimThreadTypes = options?.shimThreadTypes;
   const filterDetailedThreadEditPermissions =
     options?.filterDetailedThreadEditPermissions;
+  const filterThreadEditAvatarPermission =
+    options?.filterThreadEditAvatarPermission;
 
   const filterThreadPermissions = _omitBy(
     (v, k) =>
-      filterDetailedThreadEditPermissions &&
-      [
-        threadPermissions.EDIT_THREAD_COLOR,
-        threadPermissions.EDIT_THREAD_DESCRIPTION,
-      ].includes(k),
+      (filterDetailedThreadEditPermissions &&
+        [
+          threadPermissions.EDIT_THREAD_COLOR,
+          threadPermissions.EDIT_THREAD_DESCRIPTION,
+        ].includes(k)) ||
+      (filterThreadEditAvatarPermission &&
+        [
+          threadPermissions.EDIT_THREAD_AVATAR,
+          threadPermissionPropagationPrefixes.DESCENDANT +
+            threadPermissions.EDIT_THREAD_AVATAR,
+        ].includes(k)),
   );
 
   const members = [];
   let currentUser;
   for (const serverMember of serverThreadInfo.members) {
     if (
       filterMemberList &&
       serverMember.id !== viewerID &&
       !serverMember.role &&
       !memberHasAdminPowers(serverMember)
     ) {
       continue;
     }
     if (
       serverThreadInfo.id === genesis.id &&
       serverMember.id !== viewerID &&
       serverMember.id !== ashoat.id
     ) {
       continue;
     }
 
     const memberPermissions = filterThreadPermissions(serverMember.permissions);
 
     members.push({
       id: serverMember.id,
       role: serverMember.role,
       permissions: memberPermissions,
       isSender: serverMember.isSender,
     });
     if (serverMember.id === viewerID) {
       currentUser = {
         role: serverMember.role,
         permissions: memberPermissions,
         subscription: serverMember.subscription,
         unread: serverMember.unread,
       };
     }
   }
 
   let currentUserPermissions;
   if (currentUser) {
     currentUserPermissions = currentUser.permissions;
   } else {
     currentUserPermissions = filterThreadPermissions(
       getAllThreadPermissions(null, serverThreadInfo.id),
     );
     currentUser = {
       role: null,
       permissions: currentUserPermissions,
       subscription: {
         home: false,
         pushNotifs: false,
       },
       unread: null,
     };
   }
   if (!permissionLookup(currentUserPermissions, threadPermissions.KNOW_OF)) {
     return null;
   }
 
   let { type } = serverThreadInfo;
   if (
     shimThreadTypes &&
     shimThreadTypes[type] !== null &&
     shimThreadTypes[type] !== undefined
   ) {
     type = shimThreadTypes[type];
   }
 
   const rolesWithFilteredThreadPermissions = _mapValues(role => ({
     ...role,
     permissions: filterThreadPermissions(role.permissions),
   }))(serverThreadInfo.roles);
 
   let rawThreadInfo: any = {
     id: serverThreadInfo.id,
     type,
     name: serverThreadInfo.name,
     description: serverThreadInfo.description,
     color: serverThreadInfo.color,
     creationTime: serverThreadInfo.creationTime,
     parentThreadID: serverThreadInfo.parentThreadID,
     members,
     roles: rolesWithFilteredThreadPermissions,
     currentUser,
     repliesCount: serverThreadInfo.repliesCount,
   };
   if (!hideThreadStructure) {
     rawThreadInfo = {
       ...rawThreadInfo,
       containingThreadID: serverThreadInfo.containingThreadID,
       community: serverThreadInfo.community,
     };
   }
   const sourceMessageID = serverThreadInfo.sourceMessageID;
   if (sourceMessageID) {
     rawThreadInfo = { ...rawThreadInfo, sourceMessageID };
   }
   if (serverThreadInfo.avatar) {
     rawThreadInfo = { ...rawThreadInfo, avatar: serverThreadInfo.avatar };
   }
   if (includeVisibilityRules) {
     return {
       ...rawThreadInfo,
       visibilityRules: rawThreadInfo.type,
     };
   }
   return rawThreadInfo;
 }
 
 function threadUIName(threadInfo: ThreadInfo): string | ThreadEntity {
   if (threadInfo.name) {
     return firstLine(threadInfo.name);
   }
   const threadMembers = threadInfo.members.filter(
     memberInfo => memberInfo.role,
   );
   const memberEntities = threadMembers.map(member =>
     ET.user({ userInfo: member }),
   );
   return {
     type: 'thread',
     id: threadInfo.id,
     name: threadInfo.name,
     display: 'uiName',
     uiName: memberEntities,
   };
 }
 
 function threadInfoFromRawThreadInfo(
   rawThreadInfo: RawThreadInfo,
   viewerID: ?string,
   userInfos: UserInfos,
 ): ThreadInfo {
   let threadInfo: ThreadInfo = {
     id: rawThreadInfo.id,
     type: rawThreadInfo.type,
     name: rawThreadInfo.name,
     uiName: '',
     description: rawThreadInfo.description,
     color: rawThreadInfo.color,
     creationTime: rawThreadInfo.creationTime,
     parentThreadID: rawThreadInfo.parentThreadID,
     containingThreadID: rawThreadInfo.containingThreadID,
     community: rawThreadInfo.community,
     members: getRelativeMemberInfos(rawThreadInfo, viewerID, userInfos),
     roles: rawThreadInfo.roles,
     currentUser: getCurrentUser(rawThreadInfo, viewerID, userInfos),
     repliesCount: rawThreadInfo.repliesCount,
   };
   threadInfo = {
     ...threadInfo,
     uiName: threadUIName(threadInfo),
   };
   const { sourceMessageID, avatar } = rawThreadInfo;
   if (sourceMessageID) {
     threadInfo = { ...threadInfo, sourceMessageID };
   }
 
   if (avatar) {
     threadInfo = { ...threadInfo, avatar };
   } else if (
     rawThreadInfo.type === threadTypes.PERSONAL ||
     rawThreadInfo.type === threadTypes.PRIVATE
   ) {
     threadInfo = {
       ...threadInfo,
       avatar: getUserAvatarForThread(rawThreadInfo, viewerID, userInfos),
     };
   }
   return threadInfo;
 }
 
 function getCurrentUser(
   threadInfo: RawThreadInfo | ThreadInfo,
   viewerID: ?string,
   userInfos: UserInfos,
 ): ThreadCurrentUserInfo {
   if (!threadFrozenDueToBlock(threadInfo, viewerID, userInfos)) {
     return threadInfo.currentUser;
   }
 
   return {
     ...threadInfo.currentUser,
     permissions: {
       ...threadInfo.currentUser.permissions,
       ...disabledPermissions,
     },
   };
 }
 
 function threadIsWithBlockedUserOnly(
   threadInfo: RawThreadInfo | ThreadInfo,
   viewerID: ?string,
   userInfos: UserInfos,
   checkOnlyViewerBlock?: boolean,
 ): boolean {
   if (
     threadOrParentThreadIsGroupChat(threadInfo) ||
     threadOrParentThreadHasAdminRole(threadInfo)
   ) {
     return false;
   }
 
   const otherUserID = getSingleOtherUser(threadInfo, viewerID);
   if (!otherUserID) {
     return false;
   }
   const otherUserRelationshipStatus =
     userInfos[otherUserID]?.relationshipStatus;
 
   if (checkOnlyViewerBlock) {
     return (
       otherUserRelationshipStatus === userRelationshipStatus.BLOCKED_BY_VIEWER
     );
   }
 
   return (
     !!otherUserRelationshipStatus &&
     relationshipBlockedInEitherDirection(otherUserRelationshipStatus)
   );
 }
 
 function threadFrozenDueToBlock(
   threadInfo: RawThreadInfo | ThreadInfo,
   viewerID: ?string,
   userInfos: UserInfos,
 ): boolean {
   return threadIsWithBlockedUserOnly(threadInfo, viewerID, userInfos);
 }
 
 function threadFrozenDueToViewerBlock(
   threadInfo: RawThreadInfo | ThreadInfo,
   viewerID: ?string,
   userInfos: UserInfos,
 ): boolean {
   return threadIsWithBlockedUserOnly(threadInfo, viewerID, userInfos, true);
 }
 
 const threadTypeDescriptions: { [ThreadType]: string } = {
   [threadTypes.COMMUNITY_OPEN_SUBTHREAD]:
     'Anybody in the parent channel can see an open subchannel.',
   [threadTypes.COMMUNITY_SECRET_SUBTHREAD]:
     'Only visible to its members and admins of ancestor channels.',
 };
 
 function usersInThreadInfo(threadInfo: RawThreadInfo | ThreadInfo): string[] {
   const userIDs = new Set();
   for (const member of threadInfo.members) {
     userIDs.add(member.id);
   }
   return [...userIDs];
 }
 
 function memberIsAdmin(
   memberInfo: RelativeMemberInfo | MemberInfo,
   threadInfo: ThreadInfo | RawThreadInfo,
 ): boolean {
   return !!(
     memberInfo.role && roleIsAdminRole(threadInfo.roles[memberInfo.role])
   );
 }
 
 // Since we don't have access to all of the ancestor ThreadInfos, we approximate
 // "parent admin" as anybody with CHANGE_ROLE permissions.
 function memberHasAdminPowers(
   memberInfo: RelativeMemberInfo | MemberInfo | ServerMemberInfo,
 ): boolean {
   return !!memberInfo.permissions[threadPermissions.CHANGE_ROLE]?.value;
 }
 
 function roleIsAdminRole(roleInfo: ?RoleInfo): boolean {
   return !!(roleInfo && !roleInfo.isDefault && roleInfo.name === 'Admins');
 }
 
 function threadHasAdminRole(
   threadInfo: ?(RawThreadInfo | ThreadInfo | ServerThreadInfo),
 ): boolean {
   if (!threadInfo) {
     return false;
   }
   return !!_find({ name: 'Admins' })(threadInfo.roles);
 }
 
 function threadOrParentThreadHasAdminRole(
   threadInfo: RawThreadInfo | ThreadInfo,
 ) {
   return (
     threadMembersWithoutAddedAshoat(threadInfo).filter(member =>
       memberHasAdminPowers(member),
     ).length > 0
   );
 }
 
 function identifyInvalidatedThreads(
   updateInfos: $ReadOnlyArray<ClientUpdateInfo>,
 ): Set<string> {
   const invalidated = new Set();
   for (const updateInfo of updateInfos) {
     if (updateInfo.type === updateTypes.DELETE_THREAD) {
       invalidated.add(updateInfo.threadID);
     }
   }
   return invalidated;
 }
 
 const permissionsDisabledByBlockArray = [
   threadPermissions.VOICED,
   threadPermissions.EDIT_ENTRIES,
   threadPermissions.EDIT_THREAD_NAME,
   threadPermissions.EDIT_THREAD_COLOR,
   threadPermissions.EDIT_THREAD_DESCRIPTION,
   threadPermissions.CREATE_SUBCHANNELS,
   threadPermissions.CREATE_SIDEBARS,
   threadPermissions.JOIN_THREAD,
   threadPermissions.EDIT_PERMISSIONS,
   threadPermissions.ADD_MEMBERS,
   threadPermissions.REMOVE_MEMBERS,
 ];
 
 const permissionsDisabledByBlock: Set<ThreadPermission> = new Set(
   permissionsDisabledByBlockArray,
 );
 
 const disabledPermissions: ThreadPermissionsInfo =
   permissionsDisabledByBlockArray.reduce(
     (permissions: ThreadPermissionsInfo, permission: string) => ({
       ...permissions,
       [permission]: { value: false, source: null },
     }),
     {},
   );
 
 // Consider updating itemHeight in native/chat/chat-thread-list.react.js
 // if you change this
 const emptyItemText: string =
   `Background chats are just like normal chats, except they don't ` +
   `contribute to your unread count.\n\n` +
   `To move a chat over here, switch the “Background” option in its settings.`;
 
 function threadNoun(threadType: ThreadType, parentThreadID: ?string): string {
   if (threadType === threadTypes.SIDEBAR) {
     return 'thread';
   } else if (
     threadType === threadTypes.COMMUNITY_SECRET_SUBTHREAD &&
     parentThreadID === genesis.id
   ) {
     return 'chat';
   } else if (
     threadType === threadTypes.COMMUNITY_ROOT ||
     threadType === threadTypes.COMMUNITY_ANNOUNCEMENT_ROOT ||
     threadType === threadTypes.COMMUNITY_OPEN_SUBTHREAD ||
     threadType === threadTypes.COMMUNITY_OPEN_ANNOUNCEMENT_SUBTHREAD ||
     threadType === threadTypes.COMMUNITY_SECRET_SUBTHREAD ||
     threadType === threadTypes.COMMUNITY_SECRET_ANNOUNCEMENT_SUBTHREAD ||
     threadType === threadTypes.GENESIS
   ) {
     return 'channel';
   } else {
     return 'chat';
   }
 }
 
 function threadLabel(threadType: ThreadType): string {
   if (
     threadType === threadTypes.COMMUNITY_OPEN_SUBTHREAD ||
     threadType === threadTypes.COMMUNITY_OPEN_ANNOUNCEMENT_SUBTHREAD
   ) {
     return 'Open';
   } else if (threadType === threadTypes.PERSONAL) {
     return 'Personal';
   } else if (threadType === threadTypes.SIDEBAR) {
     return 'Thread';
   } else if (threadType === threadTypes.PRIVATE) {
     return 'Private';
   } else if (
     threadType === threadTypes.COMMUNITY_ROOT ||
     threadType === threadTypes.COMMUNITY_ANNOUNCEMENT_ROOT ||
     threadType === threadTypes.GENESIS
   ) {
     return 'Community';
   } else {
     return 'Secret';
   }
 }
 
 function useWatchThread(threadInfo: ?ThreadInfo) {
   const dispatchActionPromise = useDispatchActionPromise();
   const callFetchMostRecentMessages = useServerCall(fetchMostRecentMessages);
 
   const threadID = threadInfo?.id;
   const threadNotInChatList = !threadInChatList(threadInfo);
   React.useEffect(() => {
     if (threadID && threadNotInChatList) {
       threadWatcher.watchID(threadID);
       dispatchActionPromise(
         fetchMostRecentMessagesActionTypes,
         callFetchMostRecentMessages(threadID),
       );
     }
     return () => {
       if (threadID && threadNotInChatList) {
         threadWatcher.removeID(threadID);
       }
     };
   }, [
     callFetchMostRecentMessages,
     dispatchActionPromise,
     threadNotInChatList,
     threadID,
   ]);
 }
 
 type ExistingThreadInfoFinderParams = {
   +searching: boolean,
   +userInfoInputArray: $ReadOnlyArray<AccountUserInfo>,
 };
 type ExistingThreadInfoFinder = (
   params: ExistingThreadInfoFinderParams,
 ) => ?ThreadInfo;
 function useExistingThreadInfoFinder(
   baseThreadInfo: ?ThreadInfo,
 ): ExistingThreadInfoFinder {
   const threadInfos = useSelector(threadInfoSelector);
   const loggedInUserInfo = useLoggedInUserInfo();
   const userInfos = useSelector(state => state.userStore.userInfos);
 
   const pendingToRealizedThreadIDs = useSelector(state =>
     pendingToRealizedThreadIDsSelector(state.threadStore.threadInfos),
   );
   return React.useCallback(
     (params: ExistingThreadInfoFinderParams): ?ThreadInfo => {
       if (!baseThreadInfo) {
         return null;
       }
 
       const realizedThreadInfo = threadInfos[baseThreadInfo.id];
       if (realizedThreadInfo) {
         return realizedThreadInfo;
       }
 
       if (!loggedInUserInfo || !threadIsPending(baseThreadInfo.id)) {
         return baseThreadInfo;
       }
       const viewerID = loggedInUserInfo?.id;
 
       invariant(
         threadTypeCanBePending(baseThreadInfo.type),
         `ThreadInfo has pending ID ${baseThreadInfo.id}, but type that ` +
           `should not be pending ${baseThreadInfo.type}`,
       );
 
       const { searching, userInfoInputArray } = params;
 
       const { sourceMessageID } = baseThreadInfo;
       const pendingThreadID = searching
         ? getPendingThreadID(
             pendingThreadType(userInfoInputArray.length),
             [...userInfoInputArray.map(user => user.id), viewerID],
             sourceMessageID,
           )
         : getPendingThreadID(
             baseThreadInfo.type,
             baseThreadInfo.members.map(member => member.id),
             sourceMessageID,
           );
 
       const realizedThreadID = pendingToRealizedThreadIDs.get(pendingThreadID);
       if (realizedThreadID && threadInfos[realizedThreadID]) {
         return threadInfos[realizedThreadID];
       }
 
       const updatedThread = searching
         ? createPendingThread({
             viewerID,
             threadType: pendingThreadType(userInfoInputArray.length),
             members: [loggedInUserInfo, ...userInfoInputArray],
           })
         : baseThreadInfo;
       return {
         ...updatedThread,
         currentUser: getCurrentUser(updatedThread, viewerID, userInfos),
       };
     },
     [
       baseThreadInfo,
       threadInfos,
       loggedInUserInfo,
       pendingToRealizedThreadIDs,
       userInfos,
     ],
   );
 }
 
 type ThreadTypeParentRequirement = 'optional' | 'required' | 'disabled';
 function getThreadTypeParentRequirement(
   threadType: ThreadType,
 ): ThreadTypeParentRequirement {
   if (
     threadType === threadTypes.COMMUNITY_OPEN_SUBTHREAD ||
     threadType === threadTypes.COMMUNITY_OPEN_ANNOUNCEMENT_SUBTHREAD ||
     //threadType === threadTypes.COMMUNITY_SECRET_SUBTHREAD ||
     threadType === threadTypes.COMMUNITY_SECRET_ANNOUNCEMENT_SUBTHREAD ||
     threadType === threadTypes.SIDEBAR
   ) {
     return 'required';
   } else if (
     threadType === threadTypes.COMMUNITY_ROOT ||
     threadType === threadTypes.COMMUNITY_ANNOUNCEMENT_ROOT ||
     threadType === threadTypes.GENESIS ||
     threadType === threadTypes.PERSONAL ||
     threadType === threadTypes.PRIVATE
   ) {
     return 'disabled';
   } else {
     return 'optional';
   }
 }
 
 function threadMemberHasPermission(
   threadInfo: ServerThreadInfo | RawThreadInfo | ThreadInfo,
   memberID: string,
   permission: ThreadPermission,
 ): boolean {
   for (const member of threadInfo.members) {
     if (member.id !== memberID) {
       continue;
     }
     return permissionLookup(member.permissions, permission);
   }
   return false;
 }
 
 function useCanCreateSidebarFromMessage(
   threadInfo: ThreadInfo,
   messageInfo: ComposableMessageInfo | RobotextMessageInfo,
 ): boolean {
   const messageCreatorUserInfo = useSelector(
     state => state.userStore.userInfos[messageInfo.creator.id],
   );
 
   if (!messageInfo.id || threadInfo.sourceMessageID === messageInfo.id) {
     return false;
   }
 
   const messageCreatorRelationship = messageCreatorUserInfo?.relationshipStatus;
   const creatorRelationshipHasBlock =
     messageCreatorRelationship &&
     relationshipBlockedInEitherDirection(messageCreatorRelationship);
 
   const hasPermission = threadHasPermission(
     threadInfo,
     threadPermissions.CREATE_SIDEBARS,
   );
 
   return hasPermission && !creatorRelationshipHasBlock;
 }
 
 function useSidebarExistsOrCanBeCreated(
   threadInfo: ThreadInfo,
   messageItem: ChatMessageInfoItem,
 ): boolean {
   const canCreateSidebarFromMessage = useCanCreateSidebarFromMessage(
     threadInfo,
     messageItem.messageInfo,
   );
   return !!messageItem.threadCreatedFromMessage || canCreateSidebarFromMessage;
 }
 
 function checkIfDefaultMembersAreVoiced(threadInfo: ThreadInfo): boolean {
   const defaultRoleID = Object.keys(threadInfo.roles).find(
     roleID => threadInfo.roles[roleID].isDefault,
   );
   invariant(
     defaultRoleID !== undefined,
     'all threads should have a default role',
   );
   const defaultRole = threadInfo.roles[defaultRoleID];
   return !!defaultRole.permissions[threadPermissions.VOICED];
 }
 
 function draftKeyFromThreadID(threadID: string): string {
   return `${threadID}/message_composer`;
 }
 
 function getContainingThreadID(
   parentThreadInfo: ?ServerThreadInfo | RawThreadInfo | ThreadInfo,
   threadType: ThreadType,
 ): ?string {
   if (!parentThreadInfo) {
     return null;
   }
   if (threadType === threadTypes.SIDEBAR) {
     return parentThreadInfo.id;
   }
   if (!parentThreadInfo.containingThreadID) {
     return parentThreadInfo.id;
   }
   return parentThreadInfo.containingThreadID;
 }
 
 function getCommunity(
   parentThreadInfo: ?ServerThreadInfo | RawThreadInfo | ThreadInfo,
 ): ?string {
   if (!parentThreadInfo) {
     return null;
   }
   const { id, community, type } = parentThreadInfo;
   if (community !== null && community !== undefined) {
     return community;
   }
   if (threadTypeIsCommunityRoot(type)) {
     return id;
   }
   return null;
 }
 
 function getThreadListSearchResults(
   chatListData: $ReadOnlyArray<ChatThreadItem>,
   searchText: string,
   threadFilter: ThreadInfo => boolean,
   threadSearchResults: $ReadOnlySet<string>,
   usersSearchResults: $ReadOnlyArray<GlobalAccountUserInfo>,
   loggedInUserInfo: ?LoggedInUserInfo,
 ): $ReadOnlyArray<ChatThreadItem> {
   if (!searchText) {
     return chatListData.filter(
       item =>
         threadIsTopLevel(item.threadInfo) && threadFilter(item.threadInfo),
     );
   }
 
   const privateThreads = [];
   const personalThreads = [];
   const otherThreads = [];
   for (const item of chatListData) {
     if (!threadSearchResults.has(item.threadInfo.id)) {
       continue;
     }
     if (item.threadInfo.type === threadTypes.PRIVATE) {
       privateThreads.push({ ...item, sidebars: [] });
     } else if (item.threadInfo.type === threadTypes.PERSONAL) {
       personalThreads.push({ ...item, sidebars: [] });
     } else {
       otherThreads.push({ ...item, sidebars: [] });
     }
   }
 
   const chatItems = [...privateThreads, ...personalThreads, ...otherThreads];
   if (loggedInUserInfo) {
     chatItems.push(
       ...usersSearchResults.map(user =>
         createPendingThreadItem(loggedInUserInfo, user),
       ),
     );
   }
   return chatItems;
 }
 
 type ThreadListSearchResult = {
   +threadSearchResults: $ReadOnlySet<string>,
   +usersSearchResults: $ReadOnlyArray<GlobalAccountUserInfo>,
 };
 function useThreadListSearch(
   chatListData: $ReadOnlyArray<ChatThreadItem>,
   searchText: string,
   viewerID: ?string,
 ): ThreadListSearchResult {
   const callSearchUsers = useServerCall(searchUserCall);
   const usersWithPersonalThread = useSelector(usersWithPersonalThreadSelector);
   const searchUsers = React.useCallback(
     async (usernamePrefix: string) => {
       if (usernamePrefix.length === 0) {
         return [];
       }
 
       const { userInfos } = await callSearchUsers(usernamePrefix);
       return userInfos.filter(
         info => !usersWithPersonalThread.has(info.id) && info.id !== viewerID,
       );
     },
     [callSearchUsers, usersWithPersonalThread, viewerID],
   );
 
   const [threadSearchResults, setThreadSearchResults] = React.useState(
     new Set(),
   );
   const [usersSearchResults, setUsersSearchResults] = React.useState([]);
   const threadSearchIndex = useGlobalThreadSearchIndex();
   React.useEffect(() => {
     (async () => {
       const results = threadSearchIndex.getSearchResults(searchText);
       setThreadSearchResults(new Set(results));
       const usersResults = await searchUsers(searchText);
       setUsersSearchResults(usersResults);
     })();
   }, [searchText, chatListData, threadSearchIndex, searchUsers]);
 
   return { threadSearchResults, usersSearchResults };
 }
 
 function removeMemberFromThread(
   threadInfo: ThreadInfo,
   memberInfo: RelativeMemberInfo,
   dispatchActionPromise: DispatchActionPromise,
   removeUserFromThreadServerCall: (
     threadID: string,
     memberIDs: $ReadOnlyArray<string>,
   ) => Promise<ChangeThreadSettingsPayload>,
 ) {
   const customKeyName = `${removeUsersFromThreadActionTypes.started}:${memberInfo.id}`;
   dispatchActionPromise(
     removeUsersFromThreadActionTypes,
     removeUserFromThreadServerCall(threadInfo.id, [memberInfo.id]),
     { customKeyName },
   );
 }
 
 function switchMemberAdminRoleInThread(
   threadInfo: ThreadInfo,
   memberInfo: RelativeMemberInfo,
   isCurrentlyAdmin: boolean,
   dispatchActionPromise: DispatchActionPromise,
   changeUserRoleServerCall: (
     threadID: string,
     memberIDs: $ReadOnlyArray<string>,
     newRole: string,
   ) => Promise<ChangeThreadSettingsPayload>,
 ) {
   let newRole = null;
   for (const roleID in threadInfo.roles) {
     const role = threadInfo.roles[roleID];
     if (isCurrentlyAdmin && role.isDefault) {
       newRole = role.id;
       break;
     } else if (!isCurrentlyAdmin && roleIsAdminRole(role)) {
       newRole = role.id;
       break;
     }
   }
   invariant(newRole !== null, 'Could not find new role');
 
   const customKeyName = `${changeThreadMemberRolesActionTypes.started}:${memberInfo.id}`;
   dispatchActionPromise(
     changeThreadMemberRolesActionTypes,
     changeUserRoleServerCall(threadInfo.id, [memberInfo.id], newRole),
     { customKeyName },
   );
 }
 
 function getAvailableThreadMemberActions(
   memberInfo: RelativeMemberInfo,
   threadInfo: ThreadInfo,
   canEdit: ?boolean = true,
 ): $ReadOnlyArray<'remove_user' | 'remove_admin' | 'make_admin'> {
   const role = memberInfo.role;
   if (!canEdit || !role) {
     return [];
   }
 
   const canRemoveMembers = threadHasPermission(
     threadInfo,
     threadPermissions.REMOVE_MEMBERS,
   );
   const canChangeRoles = threadHasPermission(
     threadInfo,
     threadPermissions.CHANGE_ROLE,
   );
 
   const result = [];
   if (
     canRemoveMembers &&
     !memberInfo.isViewer &&
     (canChangeRoles || threadInfo.roles[role]?.isDefault)
   ) {
     result.push('remove_user');
   }
 
   if (canChangeRoles && memberInfo.username && threadHasAdminRole(threadInfo)) {
     result.push(
       memberIsAdmin(memberInfo, threadInfo) ? 'remove_admin' : 'make_admin',
     );
   }
 
   return result;
 }
 
 function patchThreadInfoToIncludeMentionedMembersOfParent(
   threadInfo: ThreadInfo,
   parentThreadInfo: ThreadInfo,
   messageText: string,
   viewerID: string,
 ): ThreadInfo {
   const members: UserIDAndUsername[] = threadInfo.members
     .map(({ id, username }) => (username ? { id, username } : null))
     .filter(Boolean);
   const mentionedNewMembers = extractNewMentionedParentMembers(
     messageText,
     threadInfo,
     parentThreadInfo,
   );
   if (mentionedNewMembers.length === 0) {
     return threadInfo;
   }
   members.push(...mentionedNewMembers);
   return createPendingThread({
     viewerID,
     threadType: threadTypes.SIDEBAR,
     members,
     parentThreadInfo,
     threadColor: threadInfo.color,
     name: threadInfo.name,
     sourceMessageID: threadInfo.sourceMessageID,
   });
 }
 
 function threadInfoInsideCommunity(
   threadInfo: RawThreadInfo | ThreadInfo,
   communityID: string,
 ): boolean {
   return threadInfo.community === communityID || threadInfo.id === communityID;
 }
 
 export {
   threadHasPermission,
   viewerIsMember,
   threadInChatList,
   threadIsTopLevel,
   threadIsChannel,
   threadIsSidebar,
   threadInBackgroundChatList,
   threadInHomeChatList,
   threadIsInHome,
   threadInFilterList,
   userIsMember,
   threadActualMembers,
   threadOtherMembers,
   threadIsGroupChat,
   threadIsPending,
   threadIsPendingSidebar,
   getSingleOtherUser,
   getPendingThreadID,
   pendingThreadIDRegex,
   parsePendingThreadID,
   createPendingThread,
   createUnresolvedPendingSidebar,
   extractNewMentionedParentMembers,
   createPendingSidebar,
   pendingThreadType,
   createRealThreadFromPendingThread,
   getCurrentUser,
   threadFrozenDueToBlock,
   threadFrozenDueToViewerBlock,
   rawThreadInfoFromServerThreadInfo,
   threadUIName,
   threadInfoFromRawThreadInfo,
   threadTypeDescriptions,
   usersInThreadInfo,
   memberIsAdmin,
   memberHasAdminPowers,
   roleIsAdminRole,
   threadHasAdminRole,
   identifyInvalidatedThreads,
   permissionsDisabledByBlock,
   emptyItemText,
   threadNoun,
   threadLabel,
   useWatchThread,
   useExistingThreadInfoFinder,
   getThreadTypeParentRequirement,
   threadMemberHasPermission,
   useCanCreateSidebarFromMessage,
   useSidebarExistsOrCanBeCreated,
   checkIfDefaultMembersAreVoiced,
   draftKeyFromThreadID,
   threadTypeCanBePending,
   getContainingThreadID,
   getCommunity,
   getThreadListSearchResults,
   useThreadListSearch,
   removeMemberFromThread,
   switchMemberAdminRoleInThread,
   getAvailableThreadMemberActions,
   threadMembersWithoutAddedAshoat,
   validChatNameRegex,
   chatNameMaxLength,
   patchThreadInfoToIncludeMentionedMembersOfParent,
   threadInfoInsideCommunity,
 };