I understand I have to edit boot.txt and run ./mkscr from the running archarm64 system.
(in case I want to switch/move the root filesystem to another usb/hdd/sdd partition)
But what happens in the case I made a mistake or there is a fault or hw error.
I could edit boot.txt on the SD card, e.g. with another Ubuntu/Arch x86_64 notebook.
But how to run ./mkscr without the archarm64 system ?
Thanks for any help!