feat: Implement forum feed layout and refactor space navigation logic to support new routing structure

src/app/features/forum/ForumAwareSpaceLayout.tsx

@@ -1,15 +1,31 @@
-import React from 'react';
+import React, { useMemo } from 'react';
 import { PageRoot } from '../../components/page';
 import { AnimatedOutlet } from '../../components/AnimatedOutlet';
 import { MobileFriendlyPageNav } from '../../pages/MobileFriendly';
 import { SPACE_PATH } from '../../pages/paths';
 import { Space } from '../../pages/client/space/Space';
+import { useMatrixClient } from '../../hooks/useMatrixClient';
+import { useSelectedRoom } from '../../hooks/router/useSelectedRoom';
+import { useSpace } from '../../hooks/useSpace';
+import { isForumContainer, shouldShowForumLobby } from '../../utils/room';
+import { ForumBoardProvider } from './ForumBoardContext';
 
 /**
  * Space sidebar + outlet. Forum spaces render ForumFeedSidebar in Space.tsx.
  */
 export function ForumAwareSpaceLayout() {
-  return (
+  const mx = useMatrixClient();
+  const space = useSpace();
+  const selectedRoomId = useSelectedRoom();
+
+  const scope = useMemo(() => {
+    const room = selectedRoomId ? mx.getRoom(selectedRoomId) : null;
+    const topicRoomId =
+      room && room.roomId !== space.roomId && !isForumContainer(room) ? room.roomId : undefined;
+    return { forumSpaceId: space.roomId, topicRoomId };
+  }, [mx, selectedRoomId, space.roomId]);
+
+  const layout = (
     <PageRoot
       nav={
         <MobileFriendlyPageNav path={SPACE_PATH}>
@@ -20,4 +36,14 @@ export function ForumAwareSpaceLayout() {
       <AnimatedOutlet />
     </PageRoot>
   );
+
+  if (!shouldShowForumLobby(space)) {
+    return layout;
+  }
+
+  return (
+    <ForumBoardProvider forumSpace={space} scope={scope}>
+      {layout}
+    </ForumBoardProvider>
+  );
 }

src/app/features/forum/ForumFeedPage.tsx

@@ -0,0 +1,6 @@
+import { ForumBoardDetail } from './ForumBoardDetail';
+
+/** Forum post feed in the main pane (sidebar holds filters + post list). */
+export function ForumFeedPage() {
+  return <ForumBoardDetail />;
+}

src/app/features/forum/ForumSpaceLayout.tsx

@@ -1,30 +1,8 @@
-import React, { ReactNode, useMemo } from 'react';
+import React, { ReactNode } from 'react';
-import { useMatrixClient } from '../../hooks/useMatrixClient';
-import { useSelectedRoom } from '../../hooks/router/useSelectedRoom';
-import { useSpace } from '../../hooks/useSpace';
-import { isForumContainer, shouldShowForumLobby } from '../../utils/room';
-import { ForumBoardProvider } from './ForumBoardContext';
 
-/** Shares forum board state between space sidebar and lobby/room outlet. */
+/**
+ * @deprecated Forum board context now lives in ForumAwareSpaceLayout.
+ */
 export function ForumSpaceLayout({ children }: { children: ReactNode }) {
-  const mx = useMatrixClient();
+  return children;
-  const space = useSpace();
-  const selectedRoomId = useSelectedRoom();
-
-  const scope = useMemo(() => {
-    const room = selectedRoomId ? mx.getRoom(selectedRoomId) : null;
-    const topicRoomId =
-      room && room.roomId !== space.roomId && !isForumContainer(room) ? room.roomId : undefined;
-    return { forumSpaceId: space.roomId, topicRoomId };
-  }, [mx, selectedRoomId, space.roomId]);
-
-  if (!shouldShowForumLobby(space)) {
-    return children;
-  }
-
-  return (
-    <ForumBoardProvider forumSpace={space} scope={scope}>
-      {children}
-    </ForumBoardProvider>
-  );
 }

src/app/features/forum/index.ts

@@ -3,6 +3,7 @@ export { ForumBoardDetail } from './ForumBoardDetail';
 export { ForumSortIcons } from './forumLucideIcons';
 export { ForumSpaceShell } from './ForumSpaceShell';
 export { ForumThreadDetail } from './ForumThreadDetail';
+export { ForumFeedPage } from './ForumFeedPage';
 export { ForumAwareSpaceLayout } from './ForumAwareSpaceLayout';
 export { ForumSpaceLayout } from './ForumSpaceLayout';
 export type { ForumBoardScope } from './useForumBoard';

src/app/features/lobby/Lobby.tsx

@@ -41,8 +41,7 @@ import { getSpaceRoomPath } from '../../pages/pathUtils';
 import { StateEvent } from '../../../types/matrix/room';
 import { CanDropCallback, useDnDMonitor } from './DnD';
 import { ASCIILexicalTable, orderKeys } from '../../utils/ASCIILexicalTable';
-import { getStateEvent, shouldShowForumLobby } from '../../utils/room';
+import { getStateEvent } from '../../utils/room';
-import { ForumBoardDetail } from '../forum/ForumBoardDetail';
 import { useClosedLobbyCategoriesAtom } from '../../state/hooks/closedLobbyCategories';
 import {
   makeCinnySpacesContent,
@@ -151,15 +150,7 @@ const useCanDropLobbyItem = (
   return canDrop;
 };
 
-function ForumSpaceLobby() {
-  return <ForumBoardDetail />;
-}
-
 export function Lobby() {
-  const space = useSpace();
-  if (shouldShowForumLobby(space)) {
-    return <ForumSpaceLobby />;
-  }
   return <SpaceCardLobby />;
 }
 

src/app/features/lobby/LobbyHeader.tsx

@@ -27,8 +27,12 @@ import { AddExistingModal } from '../add-existing';
 import { SpeechBubble } from '../../components/speech-bubble/SpeechBubble';
 import { SpaceOptionsMenu, type OpenAddExistingOptions } from '../space/SpaceOptionsMenu';
 import type { HierarchyItemSpace } from '../../hooks/useSpaceHierarchy';
-import { StateEvent } from '../../../types/matrix/room';
+import { useNavigate } from 'react-router-dom';
+import { getCanonicalAliasOrRoomId } from '../../utils/matrix';
+import { getSpaceFeedPath } from '../../pages/pathUtils';
+import { shouldShowForumLobby } from '../../utils/room';
 import { useForumBoardContextOptionally } from '../forum/ForumBoardContext';
+import { StateEvent } from '../../../types/matrix/room';
 
 type LobbyMenuProps = {
   powerLevels: IPowerLevels;
@@ -37,7 +41,9 @@ type LobbyMenuProps = {
 const LobbyMenu = forwardRef<HTMLDivElement, LobbyMenuProps>(
   ({ powerLevels, requestClose }, ref) => {
     const mx = useMatrixClient();
+    const navigate = useNavigate();
     const space = useSpace();
+    const isForum = shouldShowForumLobby(space);
     const creators = useRoomCreators(space);
 
     const permissions = useRoomPermissions(creators, powerLevels);
@@ -55,6 +61,11 @@ const LobbyMenu = forwardRef<HTMLDivElement, LobbyMenuProps>(
       requestClose();
     };
 
+    const handleOpenFeed = () => {
+      navigate(getSpaceFeedPath(getCanonicalAliasOrRoomId(mx, space.roomId)));
+      requestClose();
+    };
+
     return (
       <Menu ref={ref} style={{ maxWidth: toRem(160), width: '100vw' }}>
         {invitePrompt && (
@@ -67,6 +78,18 @@ const LobbyMenu = forwardRef<HTMLDivElement, LobbyMenuProps>(
           />
         )}
         <Box direction="Column" gap="100" style={{ padding: config.space.S100 }}>
+          {isForum && (
+            <MenuItem
+              onClick={handleOpenFeed}
+              size="300"
+              after={<Icon size="100" src={Icons.Thread} />}
+              radii="300"
+            >
+              <Text style={{ flexGrow: 1 }} as="span" size="T300" truncate>
+                Feed
+              </Text>
+            </MenuItem>
+          )}
           <MenuItem
             onClick={handleInvite}
             variant="Primary"

src/app/features/space/SpaceOptionsMenu.tsx

@@ -28,6 +28,10 @@ import { copyToClipboard } from '../../utils/dom';
 import { getCanonicalAliasOrRoomId, isRoomAlias } from '../../utils/matrix';
 import { getMatrixToRoom } from '../../plugins/matrix-to';
 import { getViaServers } from '../../plugins/via-servers';
+import { useNavigate } from 'react-router-dom';
+import { getSpaceFeedPath, getSpaceLobbyPath } from '../../pages/pathUtils';
+import { shouldShowForumLobby } from '../../utils/room';
+import { useSpaceFeedSelected } from '../../hooks/router/useSelectedSpace';
 
 type ForumAddOptions = {
   item: HierarchyItem;
@@ -50,6 +54,9 @@ type SpaceOptionsMenuProps = {
 export const SpaceOptionsMenu = forwardRef<HTMLDivElement, SpaceOptionsMenuProps>(
   ({ room, requestClose, forumAdd, onOpenAddExisting }, ref) => {
     const mx = useMatrixClient();
+    const navigate = useNavigate();
+    const onFeed = useSpaceFeedSelected();
+    const isForum = shouldShowForumLobby(room);
     const [hideActivity] = useSetting(settingsAtom, 'hideActivity');
     const [developerTools] = useSetting(settingsAtom, 'developerTools');
     const roomToParents = useAtomValue(roomToParentsAtom);
@@ -101,6 +108,16 @@ export const SpaceOptionsMenu = forwardRef<HTMLDivElement, SpaceOptionsMenuProps
       requestClose();
     };
 
+    const handleOpenFeed = () => {
+      navigate(getSpaceFeedPath(getCanonicalAliasOrRoomId(mx, room.roomId)));
+      requestClose();
+    };
+
+    const handleOpenManage = () => {
+      navigate(getSpaceLobbyPath(getCanonicalAliasOrRoomId(mx, room.roomId)));
+      requestClose();
+    };
+
     const handleAddTopic = () => {
       if (!forumAdd) return;
       openCreateRoomModal(forumAdd.item.roomId);
@@ -200,6 +217,30 @@ export const SpaceOptionsMenu = forwardRef<HTMLDivElement, SpaceOptionsMenuProps
               }}
             />
           )}
+          {isForum && !onFeed && (
+            <MenuItem
+              onClick={handleOpenFeed}
+              size="300"
+              after={<Icon size="100" src={Icons.Thread} />}
+              radii="300"
+            >
+              <Text style={{ flexGrow: 1 }} as="span" size="T300" truncate>
+                Feed
+              </Text>
+            </MenuItem>
+          )}
+          {isForum && onFeed && (
+            <MenuItem
+              onClick={handleOpenManage}
+              size="300"
+              after={<Icon size="100" src={Icons.Flag} />}
+              radii="300"
+            >
+              <Text style={{ flexGrow: 1 }} as="span" size="T300" truncate>
+                Manage
+              </Text>
+            </MenuItem>
+          )}
           <MenuItem
             onClick={handleMarkAsRead}
             size="300"

src/app/hooks/router/useSelectedSpace.ts

@@ -1,7 +1,6 @@
-import { useMatch, useParams } from 'react-router-dom';
+import { useLocation, useParams } from 'react-router-dom';
 import { getCanonicalAliasRoomId, isRoomAlias } from '../../utils/matrix';
 import { useMatrixClient } from '../useMatrixClient';
-import { getSpaceLobbyPath, getSpaceSearchPath } from '../../pages/pathUtils';
 
 export const useSelectedSpace = (): string | undefined => {
   const mx = useMatrixClient();
@@ -16,22 +15,18 @@ export const useSelectedSpace = (): string | undefined => {
   return spaceId;
 };
 
-export const useSpaceLobbySelected = (spaceIdOrAlias: string): boolean => {
+/** True when the current URL is the forum feed route. */
-  const match = useMatch({
+export const useSpaceFeedSelected = (): boolean => {
-    path: getSpaceLobbyPath(spaceIdOrAlias),
+  const { pathname } = useLocation();
-    caseSensitive: true,
+  return /\/feed\/?$/.test(pathname);
-    end: false,
-  });
-
-  return !!match;
 };
 
-export const useSpaceSearchSelected = (spaceIdOrAlias: string): boolean => {
+export const useSpaceLobbySelected = (_spaceIdOrAlias?: string): boolean => {
-  const match = useMatch({
+  const { pathname } = useLocation();
-    path: getSpaceSearchPath(spaceIdOrAlias),
+  return /\/lobby\/?$/.test(pathname);
-    caseSensitive: true,
+};
-    end: false,
+
-  });
+export const useSpaceSearchSelected = (_spaceIdOrAlias?: string): boolean => {
-
+  const { pathname } = useLocation();
-  return !!match;
+  return /\/search\/?$/.test(pathname);
 };

src/app/hooks/useAutoJoinSpaceRooms.ts

@@ -1,4 +1,4 @@
-import { useEffect, useRef, useCallback } from 'react';
+import { useEffect, useCallback } from 'react';
 import { MatrixClient, Room, RoomEvent } from 'matrix-js-sdk';
 import { IHierarchyRoom } from 'matrix-js-sdk/lib/@types/spaces';
 import { useAtomValue, useSetAtom } from 'jotai';
@@ -10,6 +10,7 @@ import {
   RoomNotificationMode,
 } from './useRoomsNotificationPreferences';
 import { updateJoiningProgressAtom } from '../state/joiningProgress';
+import { useMatrixClient } from './useMatrixClient';
 
 const PER_PAGE_COUNT = 100;
 const MAX_PAGES = 50;
@@ -18,6 +19,8 @@ const JOIN_DELAY_MS = 500;
 /** Join rules that allow automatic joining */
 const AUTO_JOINABLE_RULES = ['public', 'restricted', 'knock_restricted'];
 
+const processingSpaces = new Set<string>();
+
 /**
  * Extracts the server name from a Matrix room ID
  * @param roomId - The room ID (e.g., "!abc123:matrix.org")
@@ -46,12 +49,12 @@ function canAutoJoin(hierarchyRoom: IHierarchyRoom): boolean {
 }
 
 /**
- * Checks if a hierarchy item is a space
+ * Checks if a hierarchy item is a space (including m.forum category spaces)
  * @param hierarchyRoom - The room info from the space hierarchy
  * @returns Whether the item is a space
  */
 function isHierarchySpace(hierarchyRoom: IHierarchyRoom): boolean {
-  return hierarchyRoom.room_type === 'm.space';
+  return hierarchyRoom.room_type === 'm.space' || hierarchyRoom.room_type === 'm.forum';
 }
 
 /**
@@ -177,6 +180,29 @@ async function joinRoomsSequentially(
   );
 }
 
+/**
+ * Joins all auto-joinable children of a space (and nested spaces/rooms).
+ */
+export async function autoJoinSpaceChildren(
+  mx: MatrixClient,
+  spaceId: string,
+  onProgress?: ProgressCallback
+): Promise<void> {
+  if (processingSpaces.has(spaceId)) {
+    return;
+  }
+
+  processingSpaces.add(spaceId);
+
+  try {
+    const hierarchyRooms = await fetchSpaceHierarchy(mx, spaceId);
+    const childRooms = hierarchyRooms.filter((r) => r.room_id !== spaceId);
+    await joinRoomsSequentially(mx, childRooms, spaceId, onProgress);
+  } finally {
+    processingSpaces.delete(spaceId);
+  }
+}
+
 /**
  * Hook that automatically joins all accessible rooms when joining a space
  * @param mx - Matrix client instance
@@ -184,7 +210,6 @@ async function joinRoomsSequentially(
 export function useAutoJoinSpaceRooms(mx: MatrixClient): void {
   const settings = useAtomValue(settingsAtom);
   const setJoiningProgress = useSetAtom(updateJoiningProgressAtom);
-  const processingSpaces = useRef<Set<string>>(new Set());
 
   const handleSpaceJoin = useCallback(
     async (room: Room) => {
@@ -192,7 +217,7 @@ export function useAutoJoinSpaceRooms(mx: MatrixClient): void {
         return;
       }
 
-      // Only process spaces
+      // Only process spaces (includes m.forum containers)
       if (!isSpace(room)) {
         return;
       }
@@ -204,27 +229,11 @@ export function useAutoJoinSpaceRooms(mx: MatrixClient): void {
 
       const spaceId = room.roomId;
 
-      // Prevent duplicate processing
-      if (processingSpaces.current.has(spaceId)) {
-        return;
-      }
-
-      processingSpaces.current.add(spaceId);
-
       try {
-        // Fetch the space hierarchy
+        await autoJoinSpaceChildren(mx, spaceId, (current, total) => {
-        const hierarchyRooms = await fetchSpaceHierarchy(mx, spaceId);
-
-        // Filter out the space itself
-        const childRooms = hierarchyRooms.filter((r) => r.room_id !== spaceId);
-
-        // Join all accessible rooms with progress tracking
-        await joinRoomsSequentially(mx, childRooms, spaceId, (current, total) => {
           setJoiningProgress({ spaceId, progress: { current, total } });
         });
       } finally {
-        processingSpaces.current.delete(spaceId);
-        // Clear progress when done
         setJoiningProgress({ spaceId, progress: null });
       }
     },
@@ -245,3 +254,45 @@ export function useAutoJoinSpaceRooms(mx: MatrixClient): void {
     };
   }, [mx, handleSpaceJoin]);
 }
+
+/**
+ * Auto-joins space children when visiting an already-joined space (e.g. forum spaces).
+ */
+export function useAutoJoinOnSpaceVisit(space: Room | undefined): void {
+  const mx = useMatrixClient();
+  const settings = useAtomValue(settingsAtom);
+  const setJoiningProgress = useSetAtom(updateJoiningProgressAtom);
+
+  useEffect(() => {
+    if (!space || !settings.autoJoinSpaceRooms) {
+      return;
+    }
+    if (!isSpace(space)) {
+      return;
+    }
+    if (space.getMyMembership() !== Membership.Join) {
+      return;
+    }
+
+    const spaceId = space.roomId;
+    let cancelled = false;
+
+    void (async () => {
+      try {
+        await autoJoinSpaceChildren(mx, spaceId, (current, total) => {
+          if (!cancelled) {
+            setJoiningProgress({ spaceId, progress: { current, total } });
+          }
+        });
+      } finally {
+        if (!cancelled) {
+          setJoiningProgress({ spaceId, progress: null });
+        }
+      }
+    })();
+
+    return () => {
+      cancelled = true;
+    };
+  }, [space, settings.autoJoinSpaceRooms, mx, setJoiningProgress]);
+}

src/app/pages/Router.tsx

@@ -23,6 +23,7 @@ import {
   _FEATURED_PATH,
   _INVITES_PATH,
   _JOIN_PATH,
+  _FEED_PATH,
   _LOBBY_PATH,
   _NOTIFICATIONS_PATH,
   _ROOM_PATH,
@@ -37,14 +38,13 @@ import {
   getInboxNotificationsPath,
   getLoginPath,
   getOriginBaseUrl,
-  getSpaceLobbyPath,
 } from './pathUtils';
 import { ClientBindAtoms, ClientLayout, ClientRoot } from './client';
 import { Home, HomeRouteRoomProvider, HomeSearch } from './client/home';
 import { Direct, DirectCreate, DirectRouteRoomProvider } from './client/direct';
-import { RouteSpaceProvider, Space, SpaceRouteRoomProvider, SpaceSearch } from './client/space';
+import { RouteSpaceProvider, SpaceRouteRoomProvider, SpaceSearch, SpaceIndexRedirect } from './client/space';
 import { ForumAwareSpaceLayout } from '../features/forum/ForumAwareSpaceLayout';
-import { ForumSpaceLayout } from '../features/forum/ForumSpaceLayout';
+import { ForumFeedPage } from '../features/forum/ForumFeedPage';
 import { Explore, FeaturedRooms, PublicRooms } from './client/explore';
 import { Notifications, Inbox, Invites } from './client/inbox';
 import { setAfterLoginRedirectPath } from './afterLoginRedirectPath';
@@ -238,25 +238,12 @@ export const createRouter = (clientConfig: ClientConfig, screenSize: ScreenSize)
           path={SPACE_PATH}
           element={
             <RouteSpaceProvider>
-              <ForumSpaceLayout>
+              <ForumAwareSpaceLayout />
-                <ForumAwareSpaceLayout />
-              </ForumSpaceLayout>
             </RouteSpaceProvider>
           }
         >
-          {mobile ? null : (
+          <Route index element={<SpaceIndexRedirect />} />
-            <Route
+          <Route path={_FEED_PATH} element={<ForumFeedPage />} />
-              index
-              loader={({ params }) => {
-                const { spaceIdOrAlias } = params;
-                if (spaceIdOrAlias) {
-                  return redirect(getSpaceLobbyPath(spaceIdOrAlias));
-                }
-                return null;
-              }}
-              element={<WelcomePage />}
-            />
-          )}
           <Route path={_LOBBY_PATH} element={<Lobby />} />
           <Route path={_SEARCH_PATH} element={<SpaceSearch />} />
           <Route

src/app/pages/client/sidebar/SpaceTabs.tsx

@@ -37,7 +37,7 @@ import { useMatrixClient } from '../../../hooks/useMatrixClient';
 import { mDirectAtom } from '../../../state/mDirectList';
 import { roomToParentsAtom } from '../../../state/room/roomToParents';
 import { allRoomsAtom } from '../../../state/room-list/roomList';
-import { getHomePath, getSpaceLobbyPath, getSpacePath, joinPathComponent } from '../../pathUtils';
+import { getHomePath, getSpaceDefaultPath, getSpacePath, joinPathComponent } from '../../pathUtils';
 import {
   SidebarAvatar,
   SidebarItem,
@@ -1067,7 +1067,7 @@ export function SpaceTabs({ scrollRef }: SpaceTabsProps) {
       return;
     }
 
-    navigate(getSpaceLobbyPath(getCanonicalAliasOrRoomId(mx, targetSpaceId)));
+    navigate(getSpaceDefaultPath(mx, targetSpaceId));
   };
 
   const handleFolderToggle: MouseEventHandler<HTMLButtonElement> = (evt) => {
@@ -1206,7 +1206,7 @@ export function HiddenSpacesTabs() {
       return;
     }
 
-    navigate(getSpaceLobbyPath(getCanonicalAliasOrRoomId(mx, targetSpaceId)));
+    navigate(getSpaceDefaultPath(mx, targetSpaceId));
   };
 
   const handleHomeClick = () => {

src/app/pages/client/space/Space.tsx

@@ -335,7 +335,12 @@ export function Space() {
   const getToLink = (roomId: string) =>
     getSpaceRoomPath(spaceIdOrAlias, getCanonicalAliasOrRoomId(mx, roomId));
 
-  if (shouldShowForumLobby(space)) {
+  const isForum = shouldShowForumLobby(space);
+  // Forum feed unless user opened manage, search, or a room (not tied to URL alias encoding).
+  const feedActive = isForum && !lobbySelected && !searchSelected && !selectedRoomId;
+  const showForumFeedSidebar = feedActive;
+
+  if (showForumFeedSidebar) {
     return (
       <PageNav className={forumBoardCss.ForumPageNav}>
         <SpaceHeader />
@@ -346,6 +351,8 @@ export function Space() {
     );
   }
 
+  const spacePath = getCanonicalAliasOrRoomId(mx, space.roomId);
+
   return (
     <PageNav>
       <SpaceHeader />
@@ -358,38 +365,42 @@ export function Space() {
             />
           )}
           <NavCategory>
-            <NavItem variant="Background" radii="400" aria-selected={lobbySelected}>
+            {!isForum && (
-              <NavLink to={getSpaceLobbyPath(getCanonicalAliasOrRoomId(mx, space.roomId))}>
+              <>
-                <NavItemContent>
+                <NavItem variant="Background" radii="400" aria-selected={lobbySelected}>
-                  <Box as="span" grow="Yes" alignItems="Center" gap="200">
+                  <NavLink to={getSpaceLobbyPath(spacePath)}>
-                    <Avatar size="200" radii="400">
+                    <NavItemContent>
-                      <Icon src={Icons.Flag} size="100" filled={lobbySelected} />
+                      <Box as="span" grow="Yes" alignItems="Center" gap="200">
-                    </Avatar>
+                        <Avatar size="200" radii="400">
-                    <Box as="span" grow="Yes">
+                          <Icon src={Icons.Flag} size="100" filled={lobbySelected} />
-                      <Text as="span" size="Inherit" truncate>
+                        </Avatar>
-                        Lobby
+                        <Box as="span" grow="Yes">
-                      </Text>
+                          <Text as="span" size="Inherit" truncate>
-                    </Box>
+                            Lobby
-                  </Box>
+                          </Text>
-                </NavItemContent>
+                        </Box>
-              </NavLink>
+                      </Box>
-            </NavItem>
+                    </NavItemContent>
-            <NavItem variant="Background" radii="400" aria-selected={searchSelected}>
+                  </NavLink>
-              <NavLink to={getSpaceSearchPath(getCanonicalAliasOrRoomId(mx, space.roomId))}>
+                </NavItem>
-                <NavItemContent>
+                <NavItem variant="Background" radii="400" aria-selected={searchSelected}>
-                  <Box as="span" grow="Yes" alignItems="Center" gap="200">
+                  <NavLink to={getSpaceSearchPath(spacePath)}>
-                    <Avatar size="200" radii="400">
+                    <NavItemContent>
-                      <Icon src={Icons.Search} size="100" filled={searchSelected} />
+                      <Box as="span" grow="Yes" alignItems="Center" gap="200">
-                    </Avatar>
+                        <Avatar size="200" radii="400">
-                    <Box as="span" grow="Yes">
+                          <Icon src={Icons.Search} size="100" filled={searchSelected} />
-                      <Text as="span" size="Inherit" truncate>
+                        </Avatar>
-                        Message Search
+                        <Box as="span" grow="Yes">
-                      </Text>
+                          <Text as="span" size="Inherit" truncate>
-                    </Box>
+                            Message Search
-                  </Box>
+                          </Text>
-                </NavItemContent>
+                        </Box>
-              </NavLink>
+                      </Box>
-            </NavItem>
+                    </NavItemContent>
+                  </NavLink>
+                </NavItem>
+              </>
+            )}
               <PluginNavSlot location="channel-list" />
           </NavCategory>
           <NavCategory

src/app/pages/client/space/SpaceIndexRedirect.tsx

@@ -0,0 +1,26 @@
+import { useEffect } from 'react';
+import { useNavigate } from 'react-router-dom';
+import { useMatrixClient } from '../../../hooks/useMatrixClient';
+import { useSpace } from '../../../hooks/useSpace';
+import { shouldShowForumLobby } from '../../../utils/room';
+import { getSpaceDefaultPath } from '../../pathUtils';
+import { ForumFeedPage } from '../../../features/forum/ForumFeedPage';
+
+/** Sends /:spaceId/ to the forum feed or space lobby. */
+export function SpaceIndexRedirect() {
+  const mx = useMatrixClient();
+  const space = useSpace();
+  const navigate = useNavigate();
+  const isForum = shouldShowForumLobby(space);
+
+  useEffect(() => {
+    navigate(getSpaceDefaultPath(mx, space.roomId), { replace: true });
+  }, [mx, navigate, space.roomId]);
+
+  // Avoid a blank main pane while redirecting forum spaces to /feed/.
+  if (isForum) {
+    return <ForumFeedPage />;
+  }
+
+  return null;
+}

src/app/pages/client/space/SpaceProvider.tsx

@@ -1,6 +1,7 @@
 import React, { ReactNode } from 'react';
 import { useParams } from 'react-router-dom';
 import { useMatrixClient } from '../../../hooks/useMatrixClient';
+import { useAutoJoinOnSpaceVisit } from '../../../hooks/useAutoJoinSpaceRooms';
 import { useSpaces } from '../../../state/hooks/roomList';
 import { allRoomsAtom } from '../../../state/room-list/roomList';
 import { useSelectedSpace } from '../../../hooks/router/useSelectedSpace';
@@ -21,6 +22,8 @@ export function RouteSpaceProvider({ children }: RouteSpaceProviderProps) {
   const selectedSpaceId = useSelectedSpace();
   const space = mx.getRoom(selectedSpaceId);
 
+  useAutoJoinOnSpaceVisit(space ?? undefined);
+
   if (!space || !joinedSpaces.includes(space.roomId)) {
     return <JoinBeforeNavigate roomIdOrAlias={spaceIdOrAlias ?? ''} viaServers={viaServers} />;
   }

src/app/pages/client/space/index.ts

@@ -1,3 +1,4 @@
+export * from './SpaceIndexRedirect';
 export * from './SpaceProvider';
 export * from './Space';
 export * from './Search';

src/app/pages/pathUtils.ts

@@ -20,6 +20,7 @@ import {
   REGISTER_PATH,
   RESET_PASSWORD_PATH,
   ROOT_PATH,
+  SPACE_FEED_PATH,
   SPACE_LOBBY_PATH,
   SPACE_PATH,
   SPACE_ROOM_PATH,
@@ -28,6 +29,9 @@ import {
 } from './paths';
 import { trimLeadingSlash, trimTrailingSlash } from '../utils/common';
 import { HashRouterConfig } from '../hooks/useClientConfig';
+import type { MatrixClient } from 'matrix-js-sdk';
+import { getCanonicalAliasOrRoomId } from '../utils/matrix';
+import { shouldShowForumLobby } from '../utils/room';
 
 export const joinPathComponent = (path: Path): string => path.pathname + path.search + path.hash;
 
@@ -128,6 +132,21 @@ export const getSpaceLobbyPath = (spaceIdOrAlias: string): string => {
   };
   return generatePath(SPACE_LOBBY_PATH, params);
 };
+export const getSpaceFeedPath = (spaceIdOrAlias: string): string => {
+  const params = {
+    spaceIdOrAlias: encodeURIComponent(spaceIdOrAlias),
+  };
+  return generatePath(SPACE_FEED_PATH, params);
+};
+/** Forum spaces open the post feed; other spaces open the lobby. */
+export const getSpaceDefaultPath = (mx: MatrixClient, spaceId: string): string => {
+  const spaceIdOrAlias = getCanonicalAliasOrRoomId(mx, spaceId);
+  const space = mx.getRoom(spaceId);
+  if (space && shouldShowForumLobby(space)) {
+    return getSpaceFeedPath(spaceIdOrAlias);
+  }
+  return getSpaceLobbyPath(spaceIdOrAlias);
+};
 export const getSpaceSearchPath = (spaceIdOrAlias: string): string => {
   const params = {
     spaceIdOrAlias: encodeURIComponent(spaceIdOrAlias),

src/app/pages/paths.ts

@@ -22,6 +22,7 @@ export const RESET_PASSWORD_PATH = '/reset-password/:server?/';
 export const _CREATE_PATH = 'create/';
 export const _JOIN_PATH = 'join/';
 export const _LOBBY_PATH = 'lobby/';
+export const _FEED_PATH = 'feed/';
 /**
  * array of rooms and senders mxId assigned
  * to search param as string should be "," separated
@@ -57,6 +58,7 @@ export const DIRECT_ROOM_PATH = `/direct/${_ROOM_PATH}`;
 
 export const SPACE_PATH = '/:spaceIdOrAlias/';
 export const SPACE_LOBBY_PATH = `/:spaceIdOrAlias/${_LOBBY_PATH}`;
+export const SPACE_FEED_PATH = `/:spaceIdOrAlias/${_FEED_PATH}`;
 export const SPACE_SEARCH_PATH = `/:spaceIdOrAlias/${_SEARCH_PATH}`;
 export const SPACE_ROOM_PATH = `/:spaceIdOrAlias/${_ROOM_PATH}`;