If opening new files in tabs is enabled, full-screen doesn't hide the tabs, which beats the purpose of using full-sceen.

The expected result is to have the "full" full-srceen, no matter if tabs are enabled or not: as far as I know from other applications that support both tabs and full-screen view, tabs being part of the main GUI and full-screen being a way to hide that GUI, tabs should be hidden in full-screen, like it happens in internet browsers. It makes little sense to hide panels (and thus panel-tabs as it were, of other applications), window manager borders and the rest, while keeping different tabs within Okular visible.

In full-screen view tabs should be hidden - and become visible only when pushing the upper margin.