Note: This may be fixed in some Weeks, Months, or Years, so maybe you can try first:
> Thunderbird > Add-Ons > Extensions > Search for: Lightning > Install.
If you use Ubuntu-Linux or a Derivative, Lightning is not included in Thunderbird 60+ and the Update will break your Calendar (incompatible, not compatible). xul-ext-lightning is not international. Search for Add-On leads to incompatible Version. Someone told, the Beta is not recommended.
Workaround:
> Download latest Version of Thunderbird fitting for you from here: https://www.thunderbird.net/en-US/thunderbird/all/
> Open File with Archive-Program(Unzipper)
> Goto > thunderbird > distribution > extensions >
> {e2fda1a4-762b-4020-b5ad-a41df1933103}.xpi (=Lightning) > Extract
> Open your installed Thunderbird > Add-Ons > Extensions
> (Remove unwanted english Version of Lightning)
> Gear-Wheel-Button next to the Search-Box
> Install Add-on From File
> Select Download-Folder and the .xpi-File > Install
=> All your Calendar-Data should be back
Note: This may be fixed in some Weeks, Months, or Years, so maybe you can try first:
> Thunderbird > Add-Ons > Extensions > Search for: Lightning > Install.
If you use Ubuntu-Linux or a Derivative, Lightning is not included in Thunderbird 60+ and the Update will break your Calendar (incompatible, not compatible). xul-ext-lightning is not international. Search for Add-On leads to incompatible Version. Someone told, the Beta is not recommended.
Workaround: /www.thunderbir d.net/en- US/thunderbird/ all/ Program( Unzipper) 762b-4020- b5ad-a41df19331 03}.xpi (=Lightning) > Extract
> Download latest Version of Thunderbird fitting for you from here:
https:/
> Open File with Archive-
> Goto > thunderbird > distribution > extensions >
> {e2fda1a4-
> Open your installed Thunderbird > Add-Ons > Extensions
> (Remove unwanted english Version of Lightning)
> Gear-Wheel-Button next to the Search-Box
> Install Add-on From File
> Select Download-Folder and the .xpi-File > Install
=> All your Calendar-Data should be back