Comment 3 for bug 1989019

/home is mounted from /etc/fstab, by UUID, with an order number higher than /. Bog standard stuff. root is on /dev/sdd1 (my ssd) and /home is on /dev/sda1 (an old-fashioned rotating hdd).

I'll see if I can find logs, I'm a bit too tired to dig for them right now. I don't actually think the removal script really is to blame. Though I think it should never try to remove /var/lib/snapd/hostfs !

The real problem is (I think) that though /var/lib/snapd/hostfs is mounted read-only any submounts of / are not read-only. This also disables any sandboxing snap is supposed to provide imho.

I found out that /lib/systemd/system-generators/systemd-fstab-generator is the program responsible for generating the unitfile that causes /var/lib/snapd/hostfs to be mounted. But I can't find how /home gets mounted below that.

I must say I really really long for the time when mounting was just done via fastab and nothing else. All those interconnected systemd and snap parts make it mighty confusing and brittle.