This used to be an extremely useful add-on, and I used it for years. Not to be trusted blindly, of course, but it helped to have a marker to check someone out myself to make sure I wasn't taking someone at face value who was acting in bad faith. But recently the false flags have been increasingly numerous, and not in a way that could be explained by understandable accidents. About 80% of the accounts I have double checked recently (I did actually count) have been misflagged as transphobic when they are obviously and outspokenly trans friendly (friendly towards the entire trans community too, not just friendly for one group while still being hateful towards another part of the community). Moreover, every single one of the false flags I looked into myself were transmasc. I don't know if this is people coming from outside the community poisoning the well to make identifying transphobes impossible, or whether this is an(other) intra-community concerted bullying effort against other trans people whose experiences are not the same as theirs. But the end result is that the add-on is no longer usable. Sorry to see it go, but a "trans-friendly" add-on that is actively hostile to large part of the trans community is not, in fact, trans-friendly anymore. It's transphobic with exceptions.