Bookmarks bar behaviour
It would be very cool to have an option to show the bookmarks bar only on a new tab. It's shown all the time and cuts the vertical space unnecessarily. e.g. Google Chrome, Firefox with "Hide BookmarksBar" extension.
Not necessarily automatic like that - but pin/unpin button in the UI to open/close bookmarks bar with mouse/touch.
I'd use bookmarks bar HEAVILY but since it's keyboards shortcut functionality feature - I find it hard to use and boring. Pardon Opera but I simply cannot remember all tons of KB shortcuts from different apps.
Even search bar (ctrl + f) has X to close the bar, but not bookmarks bar..
The bookmarks bar is very thin. The font is so tiny that it does not need much space. I use it all the time and would not want it to disappear from all but one tab.