diff --git a/src/components/messageStream/hooks/usePostStream.ts b/src/components/messageStream/hooks/usePostStream.ts
index 646de1f..0d267f0 100644
--- a/src/components/messageStream/hooks/usePostStream.ts
+++ b/src/components/messageStream/hooks/usePostStream.ts
@@ -288,7 +288,11 @@ export function usePostStream(params: PostStreamParams): PostStreamResult {
       return;
     }
     restoredFromCacheRef.current = false;
-    setItems([]);
+    // Stale-while-revalidate: keep showing whatever items were on screen for
+    // the previous params (e.g. previous locale) while the new fetch runs.
+    // Clearing to [] here was the root cause of the language-switch flicker
+    // — the stream went blank between the click and the network response.
+    // fetchPage(true) below will replace items wholesale once data arrives.
     cursorRef.current = undefined;
     setHasMore(true);
     hasMoreRef.current = true;