Different options to synchronize Thunderbird address books.
Perhaps I’m mixing apples and oranges here, because my goals have changed over time. First I sought a way to synchronize my Thunderbird address books at home and work. More recently my employer issued me an Android based mobile phone that synchronizes its contacts with a Gmail-powered corporate mail account. So now I want to synchronize my two Thunderbird address books with my Gmail contacts. Curiously enough, the solutions I originally investigated used Gmail or IMAP generally as a hub, so perhaps my two quests aren’t so unrelated at all.
For now I’m limiting myself to what I believe is the simplest solution, a Thunderbird add-on that synchronizes the address book with Gmail’s contacts. There are also Android apps and desktop applications that purport to do what I want, but I’m trying to minimize complexity here.
For the same reason, I am for now co-mingling work and personal contacts, even though this is poor practice. What happens if your employer terminates you and locks you out of the corporate mail account without warning? This isn’t a concern with my current employment, but it does illustrate why co-mingling work and personal contacts is a bad idea. I need to find a way to keep personal contacts out of the employer-provided account and yet be available. That’s a task for another day, however.
Addressbooks Synchronizer: This isn’t the droid I’m looking for. As the add-on page says, “Not a real synchronization tool, just exchanges the files.” Included here for disambiguation.
gContactSync: What I am using. Before installing, confirm that Thunderbird (not your web browser) will accept cookies from https://account.google.com, https://google.com, and https://google.$MY_COUNTRY_TLD. To do this, in Thunderbird open Preferences – Preferences – Privacy. If you’re feeling promiscuous you could simply enable “Accept cookies from sites”. Better, leave that disabled, press the Cookie Exceptions button, and set it to allow cookies from the domains cited above. Then install gContactSync, follow its setup wizard, and you’re done. I haven’t needed to refer to it but the project has a support website.
Google Contacts: Previously the top rated add-on of its type in the Thunderbird Add-On directory but long abandoned. Included here for disambiguation.
SyncKolab has satisfied users, but in my case it scrambled my address books so badly I was forced to restore them from backup.
Zindus: Ditto SyncKolab. This add-on has since been discontinued. Included here for disambiguation.
These notes were last updated 11 November 2016 and apply to gContactSync 2.0.11 on Thunderbird 45.4/Linux.