commit e56d0877b3c7591c61b2a929f4303eabddd16ea7
Author: Dmitrii Filippov <dmfilippov@google.com>
Date:   Thu Oct 15 08:42:14 2020 +0200

    Fix crash when gr-diff-host is reloading.
    
    Issue: 13513
    Change-Id: I127768a7c2430974aa957dda9af8312874324a4a

diff --git a/polygerrit-ui/app/elements/diff/gr-diff-view/gr-diff-view.js b/polygerrit-ui/app/elements/diff/gr-diff-view/gr-diff-view.js
index 4bfa6a9..fa31d09 100644
--- a/polygerrit-ui/app/elements/diff/gr-diff-view/gr-diff-view.js
+++ b/polygerrit-ui/app/elements/diff/gr-diff-view/gr-diff-view.js
@@ -1212,7 +1212,7 @@ class GrDiffView extends KeyboardShortcutMixin(
   }
 
   _computeModeSelectHideClass(_diff) {
-    return _diff.binary ? 'hide' : '';
+    return (!_diff || _diff.binary) ? 'hide' : '';
   }
 
   _onLineSelected(e, detail) {