It's one command and you're forever in test mode[1], i.e.: don't enforce driver signatures:
bcdedit /set testsigning on
You just have to disable Secure Boot in UEFI first. (And I can confirm Windows 11 doesn't actually require Secure Boot to boot, I've had it off for months as part of win11 certification testing.)
I'm not sure but DRM might revert to lower levels (e.g.: 720p), but that also happens on macOS when you disable SIP IIRC.
True, I forgot about that detail. Basically anything that relies on driver signing enforcement for security/privacy -- DRM, anti-cheats, specific proprietary algorithms -- will deactivate when test mode is enabled, whether one-time via the bootloader or set via bcdedit.
I'm not sure but DRM might revert to lower levels (e.g.: 720p), but that also happens on macOS when you disable SIP IIRC.
1: https://docs.microsoft.com/en-us/windows-hardware/drivers/in...