tiny screw needs something
 

Not asking on a spoon forum because I dont want a bunch of replies telling me to buy some other part etc and other nonsense. (so of course I expect at least one of y'all to do just that :) )

Anyway, I use a particular selector on my AR lowers that I like because they are ambi, scalloped on the off side, and a 45 degree throw. No, none of the fun positions ...

Anyway, selector arms are attached to the main piece of the selector with kittle tiny torx head screw. And after a bunch of use they tend to get loose and sloppy and stop working properly

What can I add that will help the threads stay put but not totally lock them since I do need to take them out on occasion for very deep cleanings ... ?

I use my craft glue gun for all kinds of things like this.

Blue loktite

I sneak into my wife's clear nail polish if I want a light light hold

another vote for...

I don't use Loctite but every maker of decent quality anaerobic locking compounds typically makes a 'frequent repair" type.

A tiny cigarette