Rated 4 out of 5 stars

Used to work great, but with 60.5.2 and previous version of Thunderbird, Problems & Headaches and more Problems & Headaches, with asking for passwords and logging in over and over, other problems with importing contacts from Gmail, and others that I do not have the strength anymore to list. Honestly I do not even understand some of them . Have spent many hours looking for fixes on the Internet and most of the answers are Bull Caca. Gosh I hope this gets fixed soon, heck I will even pay or donate for real fixes. I love T-bird, but it may be time to move on, very frustrating, Oh well life goes on, maybe me too. So sorry to have to report my negativism :-((
EDITED, Been reading the reviews, think I may try going back to a previous version of T-Bird that I was reading about and renaming a file. I really do not want to quit T-Bird there is so much i like about it. I also understand what the developer is going through, that is why I got out of programming48 years ago. Take Care All of you :-)
Wm Burk

This review is for a previous version of the add-on (3.0.0). 

The password prompt's underlying cause was an interface gContactSync used that was removed in TB/Gecko (one of many...). Version 3.1.4 should work better, but requires TB 65 or later, which is still in beta.