Collapse all button

It's been requested 7 years ago, but a button to collapse all groups would be VERY nice by now! Maybe me requesting it here will finally bring the devs attention to it.

My computer crashes a lot, and I have lots of tabs/windows (that's why I use this extension in the first place). Therefore, I have tooooooooooooooons of groups of tabs that get accumulated over time. So being able to collapse all the groups to then quickly delete them would be a GODSEND.