M icrosoft's "Full screen experience" mode for handheld gaming PCs shouldn't officially be usable yet, but it turns out you can use it already if you're happy using a Preview version of Windows and ...
and then update my Windows 11 installation on my ROG Ally X to the latest available build, the 25H2 update. One little bit of 3rd party program assistance and some ‘regedit’ later, Microsoft’s Xbox ...