Free Download Axel Grude QuickFolders Pro 6.7.0 | 5 Mb
QuickFolders is a Thunderbird extension created by Alexander Malfait and Axel Grude. Folder Tabs - cuts through the clutter of the folders sidebar by having your most important folders as tabs. Open folders and sub folders, move/copy mails without scrolling around or searching. Use categories for filtering the faves!

https://quickfolders.org/index.html