I'm liking the sidebar/vertical tabs update, but something that bothers me is that it's fixed on the left side of the screen.
- I'm using 2 monitors and when Firefox is on the right monitor, I often overshoot when pointing the mouse to the tab which I want to go to or close. I think it would make a lot more sense for the sidebar to be able to lock to the right side of the screen as an option.
- When the sidebar is collapses, the close button for the tab is on the top left of it's icon which makes no sense as a windows user. The close buttons for all windows are on the top right always. When docked on screen right, the close button would be easier to reach. Overall, the design would be more "synergistical".