Used to be good, now it absolutely SUCKS

aa

The "installed" panel is a trainwreck, the only thing that it displays correctly is the number of installed styles for the current page. Some of them are always missing from the list (often enabled ones) and some from unrelated pages are visible. If I close and re-open the popup the list changes so it can't possibly be a case of too URL filters.

It's buggy and hardly works

Malware, do not install if you want to keep your data secure!

it works but the website is incredibly slow please fix it it takes like 10 minutes to load the site and it always gives bad gateway errors

I didn't install this ! It was installed by some devious means I am not aware of. I'm reporting this to Mozilla.