Midori uses gtk_window_set_hide_titlebar_when_maximized, the same as Epiphany. To quote the documentation:
This is useful for windows that don't convey any information other
than the application name in the titlebar, to put the available
screen space to better use. If the underlying window system does not
support the request, the setting will not have any effect.
In window manager terms, it sets _GTK_HIDE_TITLEBAR_WHEN_MAXIMIZED. So this is a bug in the window manager, or the way the its setup in the desktop environment. Not Midori.
Midori uses gtk_window_ set_hide_ titlebar_ when_maximized, the same as Epiphany. To quote the documentation:
This is useful for windows that don't convey any information other
than the application name in the titlebar, to put the available
screen space to better use. If the underlying window system does not
support the request, the setting will not have any effect.
In window manager terms, it sets _GTK_HIDE_ TITLEBAR_ WHEN_MAXIMIZED. So this is a bug in the window manager, or the way the its setup in the desktop environment. Not Midori.