Review for Google Calendar Tab by riversiderepeat
Rated 1 out of 5 stars
This is nothing more than Google calendar the same as it is in any browser. I use Thunderbird expressly because it allows me to manage email on or offline. This is just the web page moved into TB and will not load if you are offline. Caldav is the only useful way to deal with Google Calendars in TB.
To create your own collections, you must have a Mozilla Add-ons account.