qemu:ubuntu-16.04-32 .../tests/main/interfaces-desktop# cat /var/lib/snapd/mount/snap.test-snapd-desktop.fstab 
/var/lib/snapd/hostfs/usr/share/fonts /usr/share/fonts none bind,ro 0 0
/var/lib/snapd/hostfs/usr/local/share/fonts /usr/local/share/fonts none bind,ro 0 0
/var/lib/snapd/hostfs/var/cache/fontconfig /var/cache/fontconfig none bind,ro 0 0

qemu:ubuntu-16.04-32 .../tests/main/interfaces-desktop# cat /run/snapd/ns/snap.test-snapd-desktop.fstab
/var/lib/snapd/hostfs/var/cache/fontconfig /var/cache/fontconfig none bind,ro 0 0
/var/lib/snapd/hostfs/var/cache/fontconfig /var/cache/fontconfig none bind,ro 0 0
/var/lib/snapd/hostfs/var/cache/fontconfig /var/cache/fontconfig none bind,ro 0 0