If you say Beeflejuice three times....
autokludge
joined 2 years ago
I'm thinking you may have updated grub at some stage from Deb, and didn't have the test OS mounted at the time, or os-prober not enabled :- therefore not detected when grub.cfg was regenerated.
https://wiki.archlinux.org/title/GRUB#Detecting_other_operating_systems
https://wiki.debian.org/Grub#Dual_Boot
I ended up using rEFInd myself, as it does automatic OS detection/scans for bootable partitions.
Shin Ramyun + Easy Mac. (make with less water)