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3rd chunk of `umount.man`
539dd7d343b637a57415bca1e2375d78219cca48ec3d663600000001000008bc
 stop if any unmount operation in the chain fails for
           any reason. The relationship between mountpoints is determined by
           /proc/self/mountinfo entries. The filesystem must be specified by
           mountpoint path; a recursive unmount by device name (or UUID) is
           unsupported. Since version 2.37 it umounts also all over-mounted
           filesystems (more filesystems on the same mountpoint).

       -r, --read-only
           When an unmount fails, try to remount the filesystem read-only.

       -t, --types type...
           Indicate that the actions should only be taken on filesystems of the
           specified type. More than one type may be specified in a
           comma-separated list. The list of filesystem types can be prefixed
           with no to indicate that no action should be taken for all of the
           mentioned types. Note that umount reads information about mounted
           filesystems from kernel (/proc/mounts) and filesystem names may be
           different than filesystem names used in the /etc/fstab (e.g., "nfs4"
           vs. "nfs").

       -v, --verbose
           Verbose mode.

       -h, --help
           Display help text and exit.

       -V, --version
           Print version and exit.

NON-SUPERUSER UMOUNTS
       Normally, only the superuser can umount filesystems. However, when fstab
       contains the user option on a line, anybody can umount the corresponding
       filesystem. For more details see mount(8) man page.

       Since version 2.34 the umount command can be used to perform umount
       operation also for fuse filesystems if kernel mount table contains
       user’s ID. In this case fstab user= mount option is not required.

       Since version 2.35 umount command does not exit when user permissions
       are inadequate by internal libmount security rules. It drops suid
       permissions and continue as regular non-root user. This can be used to
       support use-cases where root permissions are not necessary (e.g., fuse
       filesystems, user namespaces, etc).

LOOP DEVICE
       The umount command will automatically detach loop device previously
       initialized by mount(8) command independently of
Title: umount Options and Non-Superuser Unmounts
Summary
The text describes the `-r` (remount read-only on failure), `-t` (specify filesystem types to unmount), `-v` (verbose mode), `-h` (help), and `-V` (version) options for the `umount` command. It also covers non-superuser unmounts, explaining that users can unmount filesystems listed in `/etc/fstab` with the `user` option. Additionally, it mentions that umount can now handle fuse filesystems without requiring the `user=` option if the kernel mount table contains the user's ID, and it drops suid permissions when user permissions are inadequate. Finally, it notes that umount automatically detaches loop devices initialized by the `mount` command.