The invisible part sucks as well. Since you do fullscreen often, you might need a convenient way to switch it on and off. F11 isn't convenient
Similarly, can you see your tabs momentarily without shifting the page layout as happens if you exit fullscreen?
Can you change the tab switching keybinds in-browser?
Can you press C to copy the current page url in fullscreen mode?
Can you have more fitting vertical tabs without the tab close button?
Etc., etc., etc.
Some of the issues are hacked around with various extensions, but then some have inpenetrable barriers coded in the awfulness that is the browser UI itself...
