dev- branch plugin forks being prompted for update
I experience the same with https://github.com/Saboteur777/craft-support forked from https://github.com/jasonmccallister/craft-support (which is a fork of https://github.com/lukeyouell/craft-support).
Using composer update will not change &quot;tracks&quot; to the original plugin, so you are safe to update, the notification is a minor annoyance, though.