Currently in Sid, osprober is no longer being enabled by default, thereby not showing your other installs on boot. This will carry through to stable on the next change.
The fix is to open the grub file in /etc/default, and then add this line;
GRUB_DISABLE_OS_PROBER=false
Then :
sudo update-grub
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Currently in Sid, osprober is no longer being enabled by default, thereby not showing your other installs on boot. This will carry through to stable on the next change.
The fix is to open the grub file in /etc/default, and then add this line;
GRUB_DISABLE_OS_PROBER=false
Then :
sudo update-grub