Ensure that pgAdmin4 shut down completely on the Quit command. Fixes #6420

docs/en_US/release_notes_5_3.rst

@@ -34,3 +34,4 @@ Bug fixes
 | `Issue #6413 <https://redmine.postgresql.org/issues/6413>`_ -  Fixed an issue where duplicate columns are visible in the browser tree, which is owned by two sequences.
 | `Issue #6416 <https://redmine.postgresql.org/issues/6416>`_ -  Added comment column in the properties panel for View and Materialized View collection node.
 | `Issue #6417 <https://redmine.postgresql.org/issues/6417>`_ -  Fixed an issue where query editor is not being closed if the user clicks on the 'Don't Save' button.
+| `Issue #6420 <https://redmine.postgresql.org/issues/6420>`_ -  Ensure that pgAdmin4 shut down completely on the Quit command.

runtime/src/js/misc.js

@@ -218,9 +218,6 @@ const cleanupAndQuitApp = () => {
   }
 
   if (pgAdminWindowObject != null) {
-    // Close the window.
-    pgAdminWindowObject.close(true);
-
     // Remove all the cookies.
     pgAdminWindowObject.cookies.getAll({}, function(cookies) {
       try {