Thank you for review.

I respect and create original QuickDrag, so we apologize, but we will not respond.
It may be created as another add-on.

2020/04/26
Added the ability to disable QuickDrag WE while the shift key is being pressed.
I would appreciate it if you could take care of it there.
Fixed an issue where the Shift key would not work when dropping in outlook.

P.S.
This one is by another person, but this one supports blacklisting.
https://addons.mozilla.org/ja/firefox/addon/glitterdrag/