Comment 22 for bug 1226912

My workaround is:
Ctrl-Alt-t
sudo killall -15 ubiquity
sudo ubiquity

Now I did get a message after the killall, I think it is on another of my pc's, which would indicate ubiquity is trying to
umount something that isn't mounted so it is stuck there. I'll see if I can find it.

I've had problems before (!) over the years with ubiquity tripping if there were other drives/partitions mounted (I have many), so before doing install I do
Ctrl-Alt-t
df
sudo umount -rl /dev/sda*
sudo umount -rl /dev/sdb*
df
to make sure nothing is mounted.