Rated 5 out of 5 stars

le Firefox user c3851c ar Ean. 21, 2022 ·

The current version of this addon has issues with tb 68 and probably doesn't install or work with tb 78, 91 and beyond. I modified the code to work with 68 and with >= 78 here: https://github.com/smitgd/addon-copyfolder-tb-esr68/tree/WL. (The 68 adaptation is on master branch.)
I tried to submit this as a new addon but it was rejected because I used the "WindowListener expermiment" to wrap the code without adapting to the new "Mail Extension API". However, updates to existing addons are OK using this method. So if the author of this addon wants to submit my version or a modified version to update this, it's OK with me.