* Activate persistence on a Tails USB install with all presets
on.
* Reboot, enable persistence. Verify via `mount` that each preset has
a mount that seem correct (e.g. "Pidgin preset =>
`/home/amnesia/.purple` has something mounted on it").
* Try read-write mode. Make sure that persistent files are writeable,
and that changes do survive reboot.
* Try read-only mode. Make sure that persistent files are writeable,
but that no changes survive reboot.
* Test adding a few custom directories.
* Turn off some persistence presets, reboot, and make sure they are
not activated.
I'll make a pause today, but will be able to do some other tests tomorrow.