diff --git a/web/redux/redux-setup.js b/web/redux/redux-setup.js
index e510beaa7..e3e8cab4e 100644
--- a/web/redux/redux-setup.js
+++ b/web/redux/redux-setup.js
@@ -1,262 +1,304 @@
 // @flow
 
 import invariant from 'invariant';
 import type { PersistState } from 'redux-persist/es/types.js';
 
 import {
   logOutActionTypes,
   deleteAccountActionTypes,
 } from 'lib/actions/user-actions.js';
 import baseReducer from 'lib/reducers/master-reducer.js';
+import { nonThreadCalendarFilters } from 'lib/selectors/calendar-filter-selectors.js';
 import { mostRecentlyReadThreadSelector } from 'lib/selectors/thread-selectors.js';
 import { isLoggedIn } from 'lib/selectors/user-selectors.js';
 import { invalidSessionDowngrade } from 'lib/shared/account-utils.js';
 import type { Shape } from 'lib/types/core.js';
 import type { DraftStore } from 'lib/types/draft-types.js';
 import type { EnabledApps } from 'lib/types/enabled-apps.js';
 import type { EntryStore } from 'lib/types/entry-types.js';
-import type { CalendarFilter } from 'lib/types/filter-types.js';
+import {
+  type CalendarFilter,
+  calendarThreadFilterTypes,
+} from 'lib/types/filter-types.js';
 import type { LifecycleState } from 'lib/types/lifecycle-state-types.js';
 import type { LoadingStatus } from 'lib/types/loading-types.js';
 import type { MessageStore } from 'lib/types/message-types.js';
 import type { UserPolicies } from 'lib/types/policy-types.js';
 import type { BaseAction } from 'lib/types/redux-types.js';
 import type { ReportStore } from 'lib/types/report-types.js';
 import type { ConnectionInfo } from 'lib/types/socket-types.js';
 import type { ThreadStore } from 'lib/types/thread-types.js';
 import type { CurrentUserInfo, UserStore } from 'lib/types/user-types.js';
 import { setNewSessionActionType } from 'lib/utils/action-utils.js';
 
 import {
   updateWindowActiveActionType,
   setDeviceIDActionType,
   updateNavInfoActionType,
   updateWindowDimensionsActionType,
+  updateCalendarCommunityFilter,
+  clearCalendarCommunityFilter,
 } from './action-types.js';
 import { reduceDeviceID } from './device-id-reducer.js';
 import reduceNavInfo from './nav-reducer.js';
 import {
   reducePrimaryIdentityPublicKey,
   setPrimaryIdentityPublicKey,
 } from './primary-identity-public-key-reducer.js';
 import { getVisibility } from './visibility.js';
+import { filterThreadIDsBelongingToCommunity } from '../selectors/calendar-selectors.js';
 import { activeThreadSelector } from '../selectors/nav-selectors.js';
 import { type NavInfo } from '../types/nav-types.js';
 
 export type WindowDimensions = { width: number, height: number };
 
 export type AppState = {
   navInfo: NavInfo,
   deviceID: ?string,
   currentUserInfo: ?CurrentUserInfo,
   draftStore: DraftStore,
   sessionID: ?string,
   entryStore: EntryStore,
   threadStore: ThreadStore,
   userStore: UserStore,
   messageStore: MessageStore,
   updatesCurrentAsOf: number,
   loadingStatuses: { [key: string]: { [idx: number]: LoadingStatus } },
   calendarFilters: $ReadOnlyArray<CalendarFilter>,
   communityIDFilter: ?string,
   urlPrefix: string,
   windowDimensions: WindowDimensions,
   cookie?: void,
   deviceToken?: void,
   baseHref: string,
   connection: ConnectionInfo,
   watchedThreadIDs: $ReadOnlyArray<string>,
   lifecycleState: LifecycleState,
   enabledApps: EnabledApps,
   reportStore: ReportStore,
   nextLocalID: number,
   dataLoaded: boolean,
   windowActive: boolean,
   userPolicies: UserPolicies,
   primaryIdentityPublicKey: ?string,
   _persist: ?PersistState,
 };
 
 export type Action =
   | BaseAction
   | { type: 'UPDATE_NAV_INFO', payload: Shape<NavInfo> }
   | {
       type: 'UPDATE_WINDOW_DIMENSIONS',
       payload: WindowDimensions,
     }
   | {
       type: 'UPDATE_WINDOW_ACTIVE',
       payload: boolean,
     }
   | {
       type: 'SET_DEVICE_ID',
       payload: string,
     }
-  | { +type: 'SET_PRIMARY_IDENTITY_PUBLIC_KEY', payload: ?string };
+  | { +type: 'SET_PRIMARY_IDENTITY_PUBLIC_KEY', payload: ?string }
+  | {
+      +type: 'UPDATE_CALENDAR_COMMUNITY_FILTER',
+      +payload: string,
+    }
+  | {
+      +type: 'CLEAR_CALENDAR_COMMUNITY_FILTER',
+      +payload: void,
+    };
 
 export function reducer(oldState: AppState | void, action: Action): AppState {
   invariant(oldState, 'should be set');
   let state = oldState;
 
   if (action.type === updateWindowDimensionsActionType) {
     return validateState(oldState, {
       ...state,
       windowDimensions: action.payload,
     });
   } else if (action.type === updateWindowActiveActionType) {
     return validateState(oldState, {
       ...state,
       windowActive: action.payload,
     });
+  } else if (action.type === updateCalendarCommunityFilter) {
+    const nonThreadFilters = nonThreadCalendarFilters(state.calendarFilters);
+
+    const threadIDs = Array.from(
+      filterThreadIDsBelongingToCommunity(
+        action.payload,
+        state.threadStore.threadInfos,
+      ),
+    );
+    return {
+      ...state,
+      calendarFilters: [
+        ...nonThreadFilters,
+        {
+          type: calendarThreadFilterTypes.THREAD_LIST,
+          threadIDs,
+        },
+      ],
+      communityIDFilter: action.payload,
+    };
+  } else if (action.type === clearCalendarCommunityFilter) {
+    const nonThreadFilters = nonThreadCalendarFilters(state.calendarFilters);
+    return {
+      ...state,
+      calendarFilters: nonThreadFilters,
+      communityIDFilter: null,
+    };
   } else if (action.type === setNewSessionActionType) {
     if (
       invalidSessionDowngrade(
         oldState,
         action.payload.sessionChange.currentUserInfo,
         action.payload.preRequestUserState,
       )
     ) {
       return oldState;
     }
     state = {
       ...state,
       sessionID: action.payload.sessionChange.sessionID,
     };
   } else if (
     (action.type === logOutActionTypes.success &&
       invalidSessionDowngrade(
         oldState,
         action.payload.currentUserInfo,
         action.payload.preRequestUserState,
       )) ||
     (action.type === deleteAccountActionTypes.success &&
       invalidSessionDowngrade(
         oldState,
         action.payload.currentUserInfo,
         action.payload.preRequestUserState,
       ))
   ) {
     return oldState;
   }
 
   if (
     action.type !== updateNavInfoActionType &&
     action.type !== setDeviceIDActionType &&
     action.type !== setPrimaryIdentityPublicKey
   ) {
     state = baseReducer(state, action).state;
   }
 
   state = {
     ...state,
     navInfo: reduceNavInfo(
       state.navInfo,
       action,
       state.threadStore.threadInfos,
     ),
     deviceID: reduceDeviceID(state.deviceID, action),
     primaryIdentityPublicKey: reducePrimaryIdentityPublicKey(
       state.primaryIdentityPublicKey,
       action,
     ),
   };
 
   return validateState(oldState, state);
 }
 
 function validateState(oldState: AppState, state: AppState): AppState {
   if (
     (state.navInfo.activeChatThreadID &&
       !state.navInfo.pendingThread &&
       !state.threadStore.threadInfos[state.navInfo.activeChatThreadID]) ||
     (!state.navInfo.activeChatThreadID && isLoggedIn(state))
   ) {
     // Makes sure the active thread always exists
     state = {
       ...state,
       navInfo: {
         ...state.navInfo,
         activeChatThreadID: mostRecentlyReadThreadSelector(state),
       },
     };
   }
 
   const activeThread = activeThreadSelector(state);
   if (
     activeThread &&
     !state.navInfo.pendingThread &&
     state.threadStore.threadInfos[activeThread].currentUser.unread &&
     getVisibility().hidden()
   ) {
     console.warn(
       `thread ${activeThread} is active and unread, ` +
         'but visibilityjs reports the window is not visible',
     );
   }
   if (
     activeThread &&
     !state.navInfo.pendingThread &&
     state.threadStore.threadInfos[activeThread].currentUser.unread &&
     typeof document !== 'undefined' &&
     document &&
     'hasFocus' in document &&
     !document.hasFocus()
   ) {
     console.warn(
       `thread ${activeThread} is active and unread, ` +
         'but document.hasFocus() is false',
     );
   }
   if (
     activeThread &&
     !getVisibility().hidden() &&
     typeof document !== 'undefined' &&
     document &&
     'hasFocus' in document &&
     document.hasFocus() &&
     !state.navInfo.pendingThread &&
     state.threadStore.threadInfos[activeThread].currentUser.unread
   ) {
     // Makes sure a currently focused thread is never unread
     state = {
       ...state,
       threadStore: {
         ...state.threadStore,
         threadInfos: {
           ...state.threadStore.threadInfos,
           [activeThread]: {
             ...state.threadStore.threadInfos[activeThread],
             currentUser: {
               ...state.threadStore.threadInfos[activeThread].currentUser,
               unread: false,
             },
           },
         },
       },
     };
   }
 
   const oldActiveThread = activeThreadSelector(oldState);
   if (
     activeThread &&
     oldActiveThread !== activeThread &&
     state.messageStore.threads[activeThread]
   ) {
     // Update messageStore.threads[activeThread].lastNavigatedTo
     state = {
       ...state,
       messageStore: {
         ...state.messageStore,
         threads: {
           ...state.messageStore.threads,
           [activeThread]: {
             ...state.messageStore.threads[activeThread],
             lastNavigatedTo: Date.now(),
           },
         },
       },
     };
   }
 
   return state;
 }