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CloseReview for Provider for Google Calendar by paulsrose
Rated 4 out of 5 stars
Stopped working the last couple of days, however it looks like it's been updated and requires you to delete your calendars and add them back again. Seems to work again now, with an updated system - hope it is stable (not sure from other comments below).
Has been a good system for using Google Calendars with Thunderbird for a long time, so hoping that continues with this update.
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