Perfect privacy friendly plugin
This Google Contacts plugin works great: it pulls user contacts effectively and asks only the minimal info from users: their contact list in read-only. I also tried the plugin from Zeroqode but it's hard coded to ask for the full profile of users and full power (e.g. birthdate, autorise app to delete contacts, etc.) which to my view is highly intrusive.
Documentation is limited on how to manage Google credentials (this has nothing to do with the app itself) and I hope the developer will add the basic explanations. In short Go to Google Console > Credentials > Add OAuth 2 and add the url from your app from where you are authenticating into the Redirect URL section.
Net, thanks for the great plugin and hope you keep updating it!!!