Add allowOverridingNativeContextMenus() (#17777)

src/vector/platform/ElectronPlatform.tsx

@@ -308,7 +308,11 @@ export default class ElectronPlatform extends VectorBasePlatform {
         return true;
     }
 
-    setNotificationCount(count: number) {
+    public allowOverridingNativeContextMenus(): boolean {
+        return true;
+    }
+
+    public setNotificationCount(count: number): void {
         if (this.notificationCount === count) return;
         super.setNotificationCount(count);