The Disks utility (gnome-disks) added this entry in /etc/fstab:
UUID=[UUID] [mount pount] auto nosuid,nodev,nofail,x-gvfs-show 0 0
Based on numerous examples and on info fstab, auto is where the filesystem type (ext4 in this case) should be, and then auto,, with a comma, should start the list of options.
But the partition is mounted at startup, so auto is working. Is fstab lax about formatting? Is the Disks utility sloppy about formatting?
(Why I care: I'm about to install Ubuntu server on a new hardware system and want to add an appropriate fstab entry manually.)