Unless they implement a feature to see what post/reasoning was used to justify the red label, and importantly with sources, then this is only going to be a hindrance to have installed if you want to find non-bigoted people. It's wrong worryingly often.

Unless you talk exclusively about issues relevant to transfemmes, then you're marked as transphobic. They're also way too quick to flag transfemmes as green just for simply being trans, often transmedicalists (aka people who think you're only "allowed" to be called trans if you get full gender affirming care, with all the gender affirming surgeries + HRT) will slip through and be green.

Likely that the people controlling it have serious biases against transmasc and enby people. That or the extension is entirely unmoderated, and has become compromised by automation/people doing false marks.

it is hardly ever accurate and mainly boils down to things the creators just disagree with

I still use it because it's the only option out there. Maybe one day it will get better and I'll change my rating back to 5 stars that it used to deserve

dead

I've had this add-on for several years, and I considered it useful until it came to light that in the past couple of years it's been marking certain people as anti-trans for... supporting nonbinary, intersex, and transmasculine people? I don't know what happened here, but this means that a tool that was once meant to help a vulnerable set of people has now turned into some sort of guessing game as to how reliable it is.
I rated this two stars instead of one because I've only encountered this issue on Tumblr whereas everywhere else (especially Twitter) it's been accurate. The only reason I still have it is to try and correct some of the falsely flagged ones I see.

EDIT: Seeing all the empty accounts here trying to claim this extension still works as intended and that the various transmasculine, nonbinary, intersex, and neopronoun users speaking up about this are wrong has made me bump this down to one star. What a shame for what used to be such a useful add-on.