Rated 4 out of 5 stars
Works great when Thunderbird updated to latest versionThis review is for a previous version of the add-on (2.69).
Here is what I replied to users both in public and in private:
V2.69 of the GB speller is now a WebExtension and it requires at least Thunderbird 60.5 (29-JAN-2019).
Mozilla triggered the updates of the speller faster than the trigger of Thunderbird.
Go to the menu: Help > About, and update from Thunderbird 60.4 to 60.5 and it should work.
Please tell me if it fixes the issue.
FOR LINUX (updates of Thunderbird can't be forced):
In the Thunderbird dictionary page, select at the bottom to see all previous releases.
Then, download 2.68, install it manually on Thunderbird and disable in it the automatic updates.
Once there is an update for Linux, go to the add-ons option on Thunderbird and re-enable its updates.
This is the best I can think of.
Tell me if it works!