diff --git a/lib/sheet_viewer_page.dart b/lib/sheet_viewer_page.dart
index c8a0901..e60d8da 100644
--- a/lib/sheet_viewer_page.dart
+++ b/lib/sheet_viewer_page.dart
@@ -91,7 +91,7 @@ class _SheetViewerPageState extends State<SheetViewerPage>
   }
 
   AppBar? buildAppBar() {
-    if (widget.config.fullscreen) {
+    if (widget.config.fullscreen && document != null) {
       return null;
     }
     return AppBar(