Docs at https://doc.turris.cz/doc/en/howto/omnia_booting_from_external_storage say that once I boot from an external device, rescue modes probably won’t work. I can confirm they don’t.
Is there a way to enable them again? E.g. manually changing some scripts, some u-boot flags or whatever?
As my eMMC is dead, I’m forced to boot from an external drive, but the rescue modes thingy was really helpful and I don’t want to say goodbye to it.