Bug 1953179 - Fix enter key handling on toolbarbuttons in tab group menu. r=dwalker,tabbrowser-reviewers

Differential Revision: https://phabricator.services.mozilla.com/D245220

browser/components/tabbrowser/content/tabgroup-menu.js

@@ -886,7 +886,11 @@
           this.close(false);
           break;
         case KeyEvent.DOM_VK_RETURN:
-          this.close();
+          // When focus is on a toolbarbutton, we need to wait for the command
+          // event, which will ultimately close the panel as well.
+          if (event.target.nodeName != "toolbarbutton") {
+            this.close();
+          }
           break;
       }
     }