EDIT: Two days later, no answer to a simple question, and this extention not working may be interferring with other extentions. "Where is the 'tab action button'?"

Original:
So, I don't really think it's one star, but I'm out of ways to get an answer. I don't see anyother way to contact the dev besides logging into their GitHub page, where the same question was asked by another user last year, with no reply.

In the support documention, it says that you can mouse over the "tab action button" to find out why a tab isn't being discarded. Where is this button? What does it look like?

Please answer; the extention used to work well for me, and now it isn't working and I can't even troubleshoot why.