dblclick is not a method, it is a type of event.
Let's say you have a button, and you wanted to manually fire that event. You could do so like this.
<button id='myButton'>Click Me!</button>
Now you can do this
var evt = new Event('dblclick');
var button = document.getElementById('myButton');
// This is where the magic happens
button.dispatchEvent(evt);
This manually fires the dblclick event.
You must call 'dispatchEvent' on a dom node, and it takes an 'Event' object.
For your use case, just replace the 'button' element with your own 'a' variable, and it should work as expected.
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