Oberon 2003 3 Jan - snippets expected in this repository.
Maybe other stuff.
DMode=00000142H
result: 640x480x32 display resolution (143H is 800x600x32)
Do that after pressing and holding SHIFT as Oberon boots (in QEMU anyway) in the text-only boot prompt part of the boot process (normally continues without stopping or prompting).
DMode is a VESA mode and can by typed there.
c to continue
w to write changes to the disk img file (raw format)