Dear bug-parted,

man parted

          set partition flag state
                     Change the state of the flag on partition to state.  Sup‐
                     ported  flags  are:  "boot",  "root",  "swap",  "hidden",
                     "raid", "lvm", "lba", "legacy_boot",  "irst",  "msftres",
                     "esp", "chromeos_kernel" and "palo".  state should be ei‐
                     ther "on" or "off".

it also works for the flag "bios_grub" not listed above

I have not checked

 
SEE ALSO
       fdisk(8),  mkfs(8),  The  parted  program  is  fully  documented in the
       info(1) format GNU partitioning software manual  which  is  distributed
       with the parted-doc Debian package.

Neill Rutherford Volunteer with Hands Together Ludlow (charity) Technology Group

Linux Mint 20.2