There is a way to add an action to a sub field of a repeater field.
The exact jQuery selector you’d use would depend on what type of sub field is involved.
I have several examples adding actions to acf fields in this repo https://github.com/Hube2/acf-dynamic-ajax-select-example including one that adds an action to a true/false field that is a sub field of a repeater https://github.com/Hube2/acf-dynamic-ajax-select-example/blob/master/unique-repeater-checkbox/unique-repeater-checkbox.js
I’m sure there are other ways to add actions other than the way I do it, but it’s what I’m used to.
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