diff --git a/web/src/plugins/streaming/StreamingTab.tsx b/web/src/plugins/streaming/StreamingTab.tsx
index 595dc75..e7ca08c 100644
--- a/web/src/plugins/streaming/StreamingTab.tsx
+++ b/web/src/plugins/streaming/StreamingTab.tsx
@@ -191,6 +191,10 @@ export default function StreamingTab({ data }: { data: any }) {
 
   // ── Viewer cleanup (only viewer PC, keeps broadcaster intact) ──
   const cleanupViewer = useCallback(() => {
+    // Exit DOM fullscreen before the viewer element is unmounted
+    if (document.fullscreenElement) {
+      document.exitFullscreen().catch(() => {});
+    }
     if (viewerPcRef.current) {
       viewerPcRef.current.close();
       viewerPcRef.current = null;