When instructing the window manager to (un)maximize a window, the resulting resolution
is recieved via an XEvent of type "ConfigureNotify".
The problem here was that these events were only handled in the `OS_X11::process_xevents()` method,
which is initially called on the first iteration of the main loop.
Because of this, the VideoMode still hadn't been updated yet when doing the boot splash setup.
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