Review for Provider for Google Calendar by Oleksandr Silver
Rated 4 out of 5 stars
can't sync Tasks correctly if there was any changes on different (2nd, 3rd) device, especially if they made at native GCal. Also can stuck with Events sync at the same conditions, but rarely
This review is for a previous version of the add-on (4.4.2).To create your own collections, you must have a Mozilla Add-ons account.