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CloseReview for Flat Folder Tree by Michael
Rated 4 out of 5 stars
User NaTong claims this function is built into TB v17 but it does not appear to be anywhere.https://addons.mozilla.org/en-US/thunderbird/addon/flat-folder-tree/reviews/476672/It does still break any folder sorting done by "Manually Sort Folders 1.1", which is unfortunate that they don't work together.
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