A simple fix would make this 5 stars.
Works with addons BSP2 and QBTF✔
BUT, should only snap to top if dragged or saved to a FOLDER, not if dragged to a position in a list.
Workaround: drag to top then drag to position.
This is annoying if you have a really long list which is positioned where you dropped a previous bookmark, and several bookmarks to add. You have to drag each new bookmark all the way down to the position and remember where it was. Or drop them all at the top and open another addon to bulk move to position.
Alternative fix= shortcut to toggle NBOT.
But limiting it to drag to FOLDER would be best.
Or better still a toggle option to drop at last position.
Bookmark Topper has the toggle.

Great idea, but it also disables moving bookmarks manually from tabs to a specific position in an open library folder, which is a Firefox feature.