https://bugzilla.kernel.org/show_bug.cgi?id=201497
--- Comment #15 from Ivan Molodetskikh (yalterz@gmail.com) --- I managed to force the kernel to use the EDID extracted via get-edid on kernel 4.18 thanks to https://bugzilla.kernel.org/show_bug.cgi?id=199799#c4 . The trick was to add video=DP-4:e to the kernel parameters, so in my case the complete addition looks like:
drm.edid_firmware=DP-4:edid/ASUS_VG248QE.bin video=DP-4:e
ASUS_VG248QE.bin was extracted with get-edid on kernel 4.18 and placed in /usr/lib/firmware/edid/. With this in place, I can use my monitor fine on the latest kernel (5.5.5).
Without this, I have the exact same issue on 5.5.5.