3.0 prerelease 40

Fixes most of the selection issues . You can now also edit JavaScript in the condition if you activate that option. I recommend restarting Thunderbird if you have a previous version installed.

To install, download filtaquilla-3.0pre40.xpi with right-click and select "save as...":

Then drag the downloaded file into the Thunderbird 78 Add-ons Manager (tools / Addons):