GRUB shows up on my external monitor, but never on the laptop monitor
@jayeff I have an issue where what you described is exactly what is happening.
I have a dual boot system with Ubuntu and windows 11, and with GRUB as the bootloader.
When I start the computer with the external monitor connected, GRUB shows up on my external monitor, but never on the laptop monitor, which is always a black screen, whether or not the external monitor is connected.
However, Fn+F9 doesn't have any effect. Any chance you have other ideas on what to try?