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
"""Redoc Open API documentation"""
    default_view = 'redoc'
    @expose('/redoc')
    def redoc(self):
        """Redoc API documentation."""
        openapi_spec_url = url_for("/api/v1./api/v1_openapi_yaml")
        return self.render_template('airflow/redoc.html', openapi_spec_url=openapi_spec_url)
class DagFilter(BaseFilter):
    """Filter using DagIDs"""
    def apply(self, query, func):  
        if current_app.appbuilder.sm.has_all_dags_access():
            return query
        filter_dag_ids = current_app.appbuilder.sm.get_accessible_dag_ids(g.user)
        return query.filter(self.model.dag_id.in_(filter_dag_ids))
class AirflowModelView(ModelView):