Rated 5 out of 5 stars

This is a great indispensable app.
But today, after the update, he was unable to synchronize contacts with Google. Google has blocked access to the address book.
Please fix the add-on. Thank you for your work.

p.s. Thanks for support. Problem resolved. (Set general.useragent.compatMode.firefox to false = the default - I had set it to true before).

This review is for a previous version of the add-on (55.5). 

restart Thunderbird !

workaround here : https://gitlab.com/CardBook/CardBook/-/issues/1172#note_512218318