diff --git a/web/selectors/calendar-selectors.js b/web/selectors/calendar-selectors.js
--- a/web/selectors/calendar-selectors.js
+++ b/web/selectors/calendar-selectors.js
@@ -54,9 +54,15 @@
   },
 );
 
+function useCommunityIsPicked(communityID: string): boolean {
+  const communityIDFilter = useSelector(state => state.communityIDFilter);
+  return communityID === communityIDFilter;
+}
+
 export {
   useFilterThreadInfos,
   useFilterThreadSearchIndex,
   filterThreadIDsBelongingToCommunitySelector,
   filterThreadIDsBelongingToCommunity,
+  useCommunityIsPicked,
 };
diff --git a/web/sidebar/community-drawer-item-handlers.react.js b/web/sidebar/community-drawer-item-handlers.react.js
--- a/web/sidebar/community-drawer-item-handlers.react.js
+++ b/web/sidebar/community-drawer-item-handlers.react.js
@@ -7,6 +7,7 @@
 
 import type { CommunityDrawerItemHandler } from './community-drawer-item-handler.react.js';
 import { updateCalendarCommunityFilter } from '../redux/action-types.js';
+import { useCommunityIsPicked } from '../selectors/calendar-selectors.js';
 import {
   useOnClickThread,
   useThreadIsActive,
@@ -44,7 +45,7 @@
       payload: threadInfo.id,
     });
   }, [dispatch, threadInfo.id]);
-  const isActive = false;
+  const isActive = useCommunityIsPicked(threadInfo.id);
 
   const handler = React.useMemo(() => ({ onClick, isActive }), [
     onClick,