Allow users to manage IMAP folders more effectively by enabling the ability to move, sort, create, delete, rename folders, and create subfolders. This feature improves organization and gives users full control over their email structure.
I think @Niborianer was referring to the mobile Thunderbird app, and perhaps K-9 Mail, not the desktop version of Thunderbird.
It would be very nice to be able to create, rename & delete IMAP folders in Thunderbird mobile. Currently I have to boot my desktop PC and use Thunderbird desktop to properly manage IMAP folders.