[Feature Request] add dialog before duplicating many (>20?) tabs

[imadnyc]

Description

I'm a tab hoarder and meant to unload all the tabs in my container, and accidentally clicked duplicate instead of unload. I'm now waiting for my computer to finish loading ~400 tabs before I can use it again. There's no one to blame but myself, but I'd appreciate the option to have a dialog to make sure I want to do that many operations.