After some more digging, I think the problem I'm having is spurious. subiquity 2280 is the version bundled with the installer. For some reason, snap in the installer is reporting 2280 is up to date, so it doesn't download the subiquity version that supports mount options.
The problem with using errors=remount-ro in the test might still be valid, though.
After some more digging, I think the problem I'm having is spurious. subiquity 2280 is the version bundled with the installer. For some reason, snap in the installer is reporting 2280 is up to date, so it doesn't download the subiquity version that supports mount options.
The problem with using errors=remount-ro in the test might still be valid, though.