Rated 5 out of 5 stars

Hello Philipp,
I use your Add-on in old TB10.0.12 ESR version. So for me it is only possible to use your Add-on in version 0.13 or 0.18pre. Both are unable to connect to google calendar since today (known issue with disabled old API from google side). May it be possible to solve the problem also for old TB10 ESR?
Otherwise I have to stop calendar function in TB...
Thanks in advance!

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

Unfortunately the Provider uses features of the Mozilla platform that are only available in Thunderbird 24 and up. Isn't there a chance that you can upgrade to at least Thunderbird 24? Its also an ESR version and contains various improvements to security and stability.