That's not totally accurate.
Lightning supports Caldav natively; as does Google. All my calendar
collections are synced with Google in this way.
The future of TB however has been in considerable doubt for a couple of
years now. Although recently mozilla have kind of said they will
continue to support it for a while it is still not out-of-the-woods...
On 03/11/17 12:51, Gary C Curtin wrote:
> Did you see what Bobby Moss wrote in LXF230, November 2017?
> "Unfortunately, Thunderbird is less straightforward; support for
> calendars at the time of writing could charitably be called
> experimental! You’ll need to install an add-on called Lightning, which
> you can obtain by heading to Tools>Add-ons>Get Add-ons. In addition,
> you’ll need to find ‘Browse all add-ons’ and search for the plugin
> before you can install it. Lightning only creates local calendars, so to
> sync with Google Calendar you need install a provider add-on too.
> Unfortunately, at the moment this is only compatible with Thunderbird if
> it’s the 32-bit incarnation and version 52.0 or earlier. But there’s a
> positive end in sight, thankfully: there have been significant
> governance changes for Thunderbird as a project and so we eagerly
> anticipate a fix."