You have script code inside of the submenu "Advanced options for Ubuntu".
A similar bug (with instructions how to fix) exists here: https://bugs.launchpad.net/grub-customizer/+bug/1505494
You have script code inside of the submenu "Advanced options for Ubuntu".
A similar bug (with instructions how to fix) exists here: https:/ /bugs.launchpad .net/grub- customizer/ +bug/1505494