This problem still persists years later! Needs to be addressed.

I would like the ability to completely hide the address bar and tabs bar at the top of the window. This would allow for viewport maximization. Currently, the only way to do this is will application fullscreen (F11), but this requires dedicating 100% of your screen to the webpage.

I often subdivide my laptop screen into quadrants when doing work, so that I can reference various things easily while working without having to entirely switch windows.

The problem is with opera in the corner, the tabs and address bar take up a considerable portion of the space, and leave the webpage contents a narrow sliver which is hard to work within.

This problem still persists years later! Needs to be addressed.