Review for Manually sort folders by lectrode
Rated 5 out of 5 stars
This addon served me well since thunderbird 68. It looks like at least a part of this functionality has been incorporated into thunderbird 115, as you can now reorder account folders by dragging accounts up and down under "Account Settings" (under the "Edit" menu in Linux). Menu bar can be accessed by pressing Alt if it is hidden.
To create your own collections, you must have a Mozilla Add-ons account.