The area above the is too large, takes up too much space. When you hover over the close button ('x') on a tab the red outline is square and looks weird on the

The area above the is too large, takes up too much space. When you hover over the close button ('x') on a tab the red outline is square and looks weird on the rounded tab. Why not make the outline rounded or make the 'x' bold on mouseover. Why use the hamburger icon and not the Firefox logo or the old Firefox button (and keep it on the left side)?