I recently changed the grub parameters to this (via grub manager):
GRUB_HIDDEN_TIMEOUT=0.0
GRUB_TIMEOUT=0.0
because I wanted GRUB to shows only if I pressed shift and I wanted my pc to automatically boot to windows if I didn't press anything.
Unfortunately I can't display GRUB by pressing Shift on start, my pc automatically boot to windows and I can't go back to Ubuntu to change the setting.
(It's normal that it boot to windows automatically because I specified it in the GRUB settings)
Do you know a way to either access grub or access Ubuntu ?
I tried to boot override from UEFI to Ubuntu but I still go to windows...
Thank you.