How To Disconnect A Mutationobserver From Inside Its Callback Function?

I'm using MutationObserver to wait for the creation of an element on the page, and then adding a button on it (with init function). I only need to add one button but mutations keep

Solution 1:

Callback function in MutationObserver is called with two arguments: mutations array and observer object itself. Because of how you wrote the code detect_node_for_buttons never gets observer object. This will do the trick:

var observer = new MutationObserver(detect_node_for_buttons);

You also have to add this argument to function declaration:

functiondetect_node_for_buttons(mutations, observer){ ... }