EDIT3: v.4.37.0.1 has now gone haywire again! Do some proper testing, guys, or just leave it alone when it's working!
Back to 3* for now.
EDIT2: v. 4.35.1.2 seems to be working! Moving up to 4 stars & will review this if it is maintained over time.
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EDIT: I GOT IT WORKING! But only by installing the PREVIOUS version. So moving up to 3 stars for now.
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I've used this for over 2 years, found it very useful & gave it 5 stars. Now it's broken: password not recognised, plugin considered "not installed" when it is, no solution from Support & no way even to delete my account! Report sent to Mozilla.