Rated 5 out of 5 stars
Not working in Thunderbird 73.0b1 for me:
The file jar:file:///Applications/Thunderbird.app/Contents/Resources/omni.ja!/chrome/messenger/content/messenger/addressbook/addressbook.xul cannot be found. Please check the location and try again.
(Update): Alas, I was afraid that was the case. Thanks for the hard work up to this point!
Thank you for pointing that out.
Unfortunately this addon only works up to version tb 70,
because mozilla has made a major change by switching from xul to xhtml for future versions.
Adjusting this change is to much work for me, so i will end the support for further versions.