I suggest to add a message prompt to confirm folder drag and drop in the folder tree.
It's too easy to make a mess in the folder tree ( especially with a bad mouse!) which will take plenty of time of IMAP server exchange.
Actually I use Disable DragAndDrop by Takayama Fumihiko, thanks to him. https://addons.thunderbird.net/fr/thunderbird/addon/disable-draganddrop-tb-v2/ but It asks for a lot of permissions.
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