Vertical tabs mode new tab button should be fixed position at the top of the tab strip

A few more things I forgot to mention:

• when enough tabs are opened, the new tab button becomes fixed position anyways! It's just that it's fixed at the bottom of the screen (which I suspect is very common for vertical tabs users because vertical tabs is meant for people that have lots of tabs open)
• another part of what I'm requesting/suggesting is: when the user clicks this new tab button that's fixed at the top of the tab strip, the new tab would open directly below it, pushing down/scrolling down the other tabs. 
• of course this would be optional because unfortunately, Edge users have gotten used to the current arrangement of the trailing new tab button, and it's not worth getting a bunch of angry user complaints by changing that on existing vertical tabs users. But I think it's worth considering that, for users that have enabled vertical tabs for the first time, it makes sense to give them this "new-tab-button-fixed-at-the-top" layout instead of the current one. And I'm very confident those users are more likely to stick with vertical tabs because having the new tab button fixed at the top is just that much better.