Developer reply by Itagaki Fumihiko
Rated 5 out of 5 stars
Itagaki Fumihiko please intervene quickly, there has been this problem since July.
Thank you
The unofficial version 3.2, created by John Bieling, does support TB115 (but only to a limited extent). It is in this very long discussion.
https://github.com/protz/Manually-Sort-Folders/issues/199
Here are my personal thoughts on the subject.
https://connect.mozilla.org/t5/ideas/thunderbird-add-ability-to-manually-sort-order-folders-in-folder/idi-p/39061
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