I was able to make it work again by first creating the directory /var/snap/lxd/common/shmounts/instances
and then removing the symbolic link /var/snap/lxd/common/lxd/shmounts
.
Now all the containers start again.
I was able to make it work again by first creating the directory /var/snap/lxd/common/shmounts/instances
and then removing the symbolic link /var/snap/lxd/common/lxd/shmounts
.
Now all the containers start again.