I’ve put my repeater listener and all belonging JS functions into the plugin’s assets. Then I’ve added a JS script asset into my FormWidget, which is inside my repeater. So every time my backend form is rendered, the JS in the FormWidget gets set and the functions inside my plugin’s assets get executed.
Of course I check, if the functions in my plugin’s assets are there and call it in the FormWidget JS like this:
if (typeof myFunction === "function") {
myFunction();
}