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
cumulative_y[task_instance.task_id].append(float(task_instance.duration + fails_total))
        
        
        y_unit = infer_time_unit([d for t in y_points.values() for d in t])
        cum_y_unit = infer_time_unit([d for t in cumulative_y.values() for d in t])
        
        chart.create_y_axis('yAxis', format='.02f', custom_format=False, label=f'Duration ({y_unit})')
        chart.axislist['yAxis']['axisLabelDistance'] = '-15'
        cum_chart.create_y_axis('yAxis', format='.02f', custom_format=False, label=f'Duration ({cum_y_unit})')
        cum_chart.axislist['yAxis']['axisLabelDistance'] = '-15'
        for task_id in x_points:
            chart.add_serie(
                name=task_id,
                x=x_points[task_id],
                y=scale_time_units(y_points[task_id], y_unit),
            )
            cum_chart.add_serie(
                name=task_id,
                x=x_points[task_id],
                y=scale_time_units(cumulative_y[task_id], cum_y_unit),
            )
        dates = sorted({ti.execution_date for ti in task_instances})
        max_date = max(ti.execution_date for ti in task_instances) if dates else None
        session.commit()
        form = DateTimeWithNumRunsForm(
            data={
                'base_date': max_date or timezone.utcnow(),
                'num_runs': num_runs,
            }
        )