Rated 5 out of 5 stars

to use google contacts
1.install tbsync
2. install "Provider for CalDAV & CardDAV"
3. add an account > CardDav
4. manual configuration
5. carddav server url : use this config url from google https://www.googleapis.com/.well-known/carddav
5. enter your google credentials etc...
(see https://webdav.io/google-carddav-url/)
in the account tab of tbsync you will get sthg like
carddav url : https://www.googleapis.com/carddav/v1/principals/[email protected]/lists/default/

This review is for a previous version of the add-on (2.19).