Awesome add on but left 2 things in my opinion for it can have 5 stars, the way to change color schemes, not so dark or default and close tabs with middle click mouse. I'll change it to 5 stars when we have this feature.

no new functions (for example export in different formats), visual/selection lag .

Nice. Basically required for Firefox use. (Firefox really needs to add this absolutely normal tab-handling functionality to the browser--Chrome's had it since the beginning.)

This may be the same as a previously existing extension called "Select and Do"? (It's been a while since I used Firefox, but this came up when I searched for that extension which I previously used for this purpose.)

I feel like I may have preferred that one, but I might be completely making this up and this may be the exact same extension with a different name. Who knows.

Does what it says it does, no bullshit

Does not move the whole selection of tabs to a new window, only up to 28 tabs. Seems to be limited in how many tabs it can handle. That's pretty poor for a "multiple tab handler".