Rated 5 out of 5 stars

fantastic add on, however recently I have had trouble with repeating calendar events.
How to reproduce the bug:
Open Thunderbird, create a new date that is recurring weekly, but has a few dates missing (e.g. an event that takes place every wednesday from 12:00 to 14:00 o'clock, but not during Christmas break).
Now go ahead and delete a couple of dates from the series (but NOT the whole series, just a few singular dates, e.g. 2 between Christmas and New Year).

Now the bug happens.
If you turn a regular re-occuring series into an irregular series,
A little bit later (~1 hour) the series will vanish from your Thunderbird.

BUT if you log into your calendar via browser, the series is still there, but in Thunderbird they stay gone.

This review is for a previous version of the add-on (1.0.2).