To avoid further confusion: lightning 5.4 is only intended to work with thunderbird 52.0! for whatever reason mozilla simply does not provide lightning as add-on anymore.ĮDIT: have a look at the last section of this answer. so now there is a mismatch between the Thunderbird version in the repositories and the add-on provided by Mozilla lightning) in their repositories.ĭebian also provides lang-packs ( lightning-l10n-.) for lightning and ubuntu does not. Yes, both do not, but they provide lightning via a seperate package ( xul-ext-lightning resp. Mozilla provides Lightning as bundled in the last versions, but Ubuntu (and Debian?) package do not Remove the add-on and wait until a future Thunderbird apt package provides it integrated (as Mozilla bundles it for other platforms).Keep the Mozilla add-on until the mismatch with Thunderbird apt package is fixed.So, which is the proper 'future-proof' way to install Lightning in Mozilla Thunderbird from now on (as intended by Ubuntu maintainers)? Another is to delete the non-compatible Ligthning add-on and install a separate package ( xul-ext-lightning) via apt, but it is not localised ( only available in English since at least 2010).

One suggested option is to search and install beta releases provided by Mozilla, but it looks as a workaround (future automatic updates are compromised). Mozilla provides Lightning as bundled in the last versions, but Ubuntu (and Debian?) package do not, so now there is a mismatch between the Thunderbird version in the repositories and the add-on provided by Mozilla (5.4, only useful for Thunderbird 52). A recent update of Thunderbird in Ubuntu (version 60.2.1) broke the Lightning calendar installed as add-on.

What is mozilla thunderbird lightning