Rated 4 out of 5 stars

Please update it for TB68.

This review is for a previous version of the add-on (1.2.5.2). 

Did. While the new version on thunderbird.net is still in review and waiting for approval from the Thunderbird team, so it can go public here on this page, you can in the meantime download it from my webiste and install it manually : https://lab5.ch/colored-folders