fix(channels): render rooms list non-virtualized so re-picking a workspace on native doesn't strand the list empty after a remount

src/app/pages/client/channels/ChannelsList.tsx

@@ -3,14 +3,12 @@ import { useTranslation } from 'react-i18next';
 import { useAtom, useAtomValue } from 'jotai';
 import { Box, config } from 'folds';
 import { Room } from 'matrix-js-sdk';
-import { useVirtualizer } from '@tanstack/react-virtual';
 import { useMatrixClient } from '../../../hooks/useMatrixClient';
 import { mDirectAtom } from '../../../state/mDirectList';
 import { NavCategory, NavCategoryHeader } from '../../../components/nav';
 import { getCanonicalAliasOrRoomId } from '../../../utils/matrix';
 import { useSelectedRoom } from '../../../hooks/router/useSelectedRoom';
 import { useSpace } from '../../../hooks/useSpace';
-import { VirtualTile } from '../../../components/virtualizer';
 import { RoomNavCategoryButton, RoomNavItem } from '../../../features/room-nav';
 import { makeNavCategoryId } from '../../../state/closedNavCategories';
 import { roomToUnreadAtom } from '../../../state/room/roomToUnread';
@@ -26,19 +24,28 @@ import {
 import { getChannelsRoomPath } from '../../pathUtils';
 
 type ChannelsListProps = {
-  // Scroll container ref — owned by the parent `PageNavContent` so virtualizer
+  // Kept for API compatibility with PageNavContent's scrollRef wiring even
-  // measures the actual scrollable element instead of an inner div nested
+  // though the list itself no longer virtualizes — parent still passes the
-  // inside `<Scroll>`. Wrong scroll target → clientHeight reads as 0 →
+  // ref so other consumers (StreamHeader curtain gesture) can read it.
-  // virtualizer renders no rows. Match `Space.tsx` pattern.
   scrollRef: MutableRefObject<HTMLDivElement | null>;
 };
 
 // Joined-hierarchy list rendered inside the channels left pane. Mirrors the
-// scaffold of `Space.tsx` (virtualized hierarchy of joined rooms grouped by
+// scaffold of `Space.tsx` (hierarchy of joined rooms grouped by sub-spaces)
-// sub-spaces) but routes selections through the /channels/<space>/<room>/
+// but routes selections through the /channels/<space>/<room>/ path so the
-// path so the room timeline opens inside the channels surface, not the
+// room timeline opens inside the channels surface, not the legacy
-// legacy /<spaceId>/<room>/ tree.
+// /<spaceId>/<room>/ tree.
-export function ChannelsList({ scrollRef }: ChannelsListProps) {
+//
+// NOT virtualized on purpose. Lists in the channels pane are bounded (one
+// orphan workspace + its joined rooms — typically tens, not thousands),
+// and @tanstack/react-virtual had a fragile race here with folds' Scroll
+// component: every re-render of `<Scroll>` creates a fresh inline ref
+// callback, React 18 detaches the old callback (nulling scrollRef.current)
+// before children's useLayoutEffects run, and the virtualizer's
+// `_willUpdate` saw null on its first chance to subscribe — leaving the
+// list permanently empty on the 2nd+ remount of the same workspace. Plain
+// `.map()` sidesteps the whole subscription dance.
+export function ChannelsList({ scrollRef: _scrollRef }: ChannelsListProps) {
   const { t } = useTranslation();
   const mx = useMatrixClient();
   const space = useSpace();
@@ -84,13 +91,6 @@ export function ChannelsList({ scrollRef }: ChannelsListProps) {
     )
   );
 
-  const virtualizer = useVirtualizer({
-    count: hierarchy.length,
-    getScrollElement: () => scrollRef.current,
-    estimateSize: () => 0,
-    overscan: 10,
-  });
-
   const handleCategoryClick = useCategoryHandler(setClosedCategories, (categoryId) =>
     closedCategories.has(categoryId)
   );
@@ -100,26 +100,16 @@ export function ChannelsList({ scrollRef }: ChannelsListProps) {
 
   return (
     <Box direction="Column" gap="300">
-      <NavCategory
+      <NavCategory>
-        style={{
+        {hierarchy.map((item, index) => {
-          height: virtualizer.getTotalSize(),
+          const { roomId } = item;
-          position: 'relative',
-        }}
-      >
-        {virtualizer.getVirtualItems().map((vItem) => {
-          const { roomId } = hierarchy[vItem.index] ?? {};
           const room = mx.getRoom(roomId);
           if (!room) return null;
 
           if (room.isSpaceRoom()) {
             const categoryId = makeNavCategoryId(space.roomId, roomId);
             return (
-              <VirtualTile
+              <div key={roomId} style={{ paddingTop: index === 0 ? undefined : config.space.S400 }}>
-                virtualItem={vItem}
-                key={vItem.index}
-                ref={virtualizer.measureElement}
-              >
-                <div style={{ paddingTop: vItem.index === 0 ? undefined : config.space.S400 }}>
                 <NavCategoryHeader>
                   <RoomNavCategoryButton
                     data-category-id={categoryId}
@@ -130,17 +120,12 @@ export function ChannelsList({ scrollRef }: ChannelsListProps) {
                   </RoomNavCategoryButton>
                 </NavCategoryHeader>
               </div>
-              </VirtualTile>
             );
           }
 
           return (
-            <VirtualTile
-              virtualItem={vItem}
-              key={vItem.index}
-              ref={virtualizer.measureElement}
-            >
             <RoomNavItem
+              key={roomId}
               room={room}
               selected={selectedRoomId === roomId}
               showAvatar={mDirects.has(roomId)}
@@ -148,11 +133,9 @@ export function ChannelsList({ scrollRef }: ChannelsListProps) {
               linkPath={getToLink(roomId)}
               notificationMode={getRoomNotificationMode(notificationPreferences, room.roomId)}
             />
-            </VirtualTile>
           );
         })}
       </NavCategory>
     </Box>
   );
 }
-