Something about this extension's most recent updates makes Firefox no longer prefill passwords from its own database. That means that while it does fill in, less conveniently because there's an extra authentication step, a few passwords that I only ever had on my iPhone, I've lost access to passwords prefilling correctly on more than 500 websites.

It's rare the software that has the net effect of doing the exact opposite of what it's supposed to do, to the tune of dozens and dozens of times in the wrong direction than any movement in the correct one, but mathematically here we are. Uninstall from me.