Review for Disable DragAndDrop (for Thunderbird 68+) by stachu541-whyisthisalreadyinuse
Rated 5 out of 5 stars
I've been looking for this option including asking chat GPT that was making up some settings that do not exist. Not sure how I finally stumbled upon this addon but FINALLY!
To create your own collections, you must have a Mozilla Add-ons account.