tails-installer fails to install to already mounted devices
This was discovered by the automated test suite for feature/buster since we started auto-mounting removable storage when it is plugged (#15900 (closed)). It also affects stable but since we don't auto-mount the automated test suite didn't discover it. We probably have had this bug for years.
Its graphical log says:
Unmounting mounted filesystems on "/dev/sda1"
Unmounting mounted filesystems on "/dev/sda1"
Could not get udisks object /dev/sda
Tails installation failed!
Could not get udisks object /dev/sdaI'll dump a full --verbose log here if I don't manage to solve it fast.
Edited by anonym