New Google Calendar Provider for Thunderbird/Lightning

Finally a Google Calendar Provider for Thunderbird/Lightning has been released that's based on the gdata api, and not just a network XML link.
Problem with the later approach was - to me - that you needed to add each of your calendars separately via their URLs. That seemed to have performance impacts as well. I had about seven such calendars, and it significantly (with my other CalDAV calendars) slowed down Thunderbird start-up time.

When the new provider was released a couple of days ago, I first really noticed, because it forced me - with a separate pop-up - to authorize it for my Google account. With seven calendars this step kept popping up - seven times, of course - but still for the old calendar URLs.
Performance was really nasty...  Thunderbird was unusable essentially.

For some weird reason, I tried a "New Calendar" > "On the Network" > "Google Calendar" and found, that it was actually letting my select Google calendars by account, instead of just letting me add the XML link per calendar like the previous version.

So first thing, delete all my old Google calendars in Lightning, and try the "New Calendar" > "On the Network" > "Google Calendar" again, with my Google account, and voila, it presented all the calendars I had on Google. With the color as on the web. I only needed to select the ones I wanted in Lightning, and that was it.

Should have been like this from the start :)

Thunderbird start-up performance is back to a couple of seconds now (from about 1 minute+)