I have just installed Xubuntu 17.10, and I have noticed that grub did not detect my previous Manjaro installation (which is still intact in another partition, I checked).
How do I get grub to add Manjaro as booting option? Please provide easy-to-follow instructions, as I am a newbie.
Thanks
EDIT 1: I have already tried using sudo update-grub and sudo update-grub2, rebooting after using each one, and it made no difference at all. Moreover, I want to point out that at boot time I do not see the grub menu -- the screen is blank for a few seconds, and then Xubuntu boots normally.
Edit 2: I don't know if this matters, but the filesystem of my Manjaro OS partition is btrfs