In the UI it would be nice to duplicate the selected connection, in the menu "With Selected". 

The copy would be set with the same name plus some suffix (_copy, _1, whatever) and it is useful for when you have a connection with all equal fields except something in a particular one. 
airflow/www/views.py
"""Clears the action."""
        try:
            dag_to_tis = collections.defaultdict(list)
            for ti in task_instances:
                dag = current_app.dag_bag.get_dag(ti.dag_id)
                dag_to_tis[dag].append(ti)
            for dag, task_instances_list in dag_to_tis.items():
                models.clear_task_instances(task_instances_list, session, dag=dag)
            session.commit()
            flash(f"{len(task_instances)} task instances have been cleared")
        except Exception as e:  
            flash(f'Failed to clear task instances: "{e}"', 'error')
        self.update_redirect()
        return redirect(self.get_redirect())
    @provide_session
    def set_task_instance_state(self, tis, target_state, session=None):