Review for CardBook by Superhog
Rated 1 out of 5 stars
CardBook updated today, running 128esr.. Sub-categories are missing and it no longer syncs to Apple. Trying to go back to default Thunderbird app and loosing the entire evening...
Worth noting is the forum link: https://cardbook.icu/forum/ doesn't work..
To create your own collections, you must have a Mozilla Add-ons account.