Review for CardBook by StratosL
Rated 5 out of 5 stars
Successfully retrieved my Gmail contacts, but not my O365 business contacts. I did manage to import those into CardBook through DavMail as a Carddav address book.
It would be fantastic if I could connect to O365 Business and also to download exchange teams as categories.
To create your own collections, you must have a Mozilla Add-ons account.