Ensure that the query tool should display the proper error message while terminating the active session. Fixes #3591

docs/en_US/release_notes_4_23.rst

@@ -24,6 +24,7 @@ Housekeeping
 Bug fixes
 *********
 
+| `Issue #3591 <https://redmine.postgresql.org/issues/3591>`_ -  Ensure that the query tool should display the proper error message while terminating the active session.
 | `Issue #3669 <https://redmine.postgresql.org/issues/3669>`_ -  Ensure that proper error should be displayed for the deleted node.
 | `Issue #3787 <https://redmine.postgresql.org/issues/3787>`_ -  Disabled the Stop process button after clicking it and added a message 'Terminating the process...' to notify the user.
 | `Issue #4226 <https://redmine.postgresql.org/issues/4226>`_ -  Fixed an issue where select all checkbox only selects the first 50 tables.

web/pgadmin/utils/driver/psycopg2/connection.py

@@ -1404,15 +1404,19 @@ Failed to reset the connection to the server due to following error:
         is_error = False
         try:
             status = self._wait_timeout(self.conn)
+        except psycopg2.OperationalError as op_er:
+            errmsg = \
+                self._formatted_exception_msg(op_er, formatted_exception_msg)
+            is_error = True
         except psycopg2.Error as pe:
+            errmsg = self._formatted_exception_msg(pe, formatted_exception_msg)
+            is_error = True
             if self.conn.closed:
                 raise ConnectionLost(
                     self.manager.sid,
                     self.db,
                     self.conn_id[5:]
                 )
-            errmsg = self._formatted_exception_msg(pe, formatted_exception_msg)
-            is_error = True
         except OSError as e:
             # Bad File descriptor
             if e.errno == 9: