The documentation https://clearlinux.org/documentation/clear-linux/tutorials/multi-boot/multi-boot-restore-bl has been removed but it’s archived in Restore the Clear Linux* OS boot loader | Clear Linux* Project
(I needed it because on my Panasonic CF-SZ5 the installer did not activate the ESP in UEFI … no problem on another UEFI machine …)
(I made a triple boot with Windows and MX Linux on my CF-SZ5 … I think the MX Linux installer wanted to use the Clear Linux ESP but I told it to use a newer one … I am going to check if I can make the MX Linux boot menu (grub) offer me the option to boot Clear Linux … otherwise I need to go in the BIOS settings to activate Clear Linux “Linux Bootloader” ESP (or sthing like that) and it’s a bit cumbersome …)