GRUB does not show other installed OS after EndeavourOS installation

Hi! Welcome to the forum! :enos:

Is your issue because grub is not running os prober? :thinking:

You may try this:

sudo nano /etc/default/grub

Go to the end of the file, and type this in a new line:

GRUB_DISABLE_OS_PROBER=false

Ctrl + s to save

Ctrl + x to exit

Now update Grub configuration:

sudo grub-mkconfig -o /boot/grub/grub.cfg

It may take some time because os-prober is slow. Be patient!

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