FreeCommander Forum

Option to hide main toolbar, image toolbar, and menu in viewer window, same as in the main FC window, it could be accessible also from the context menu.

Option to hide main toolbar, image toolbar, and menu in fullscreen, independently on window, it could be accessible also from the context menu.

Or/and auto-hide any toolbar(s) and menu in fullscreen mode.

Yes

Just like in case of web-browsers, in which you can temporarily increase to screen area for viewed content

Added to the first post, just I'm not sure if it's possible:

Or/and auto-hide any toolbar(s) and menu in fullscreen mode, as option.