when mounting an .img via fstab, it shows duplicate in caja file manager

I have done [these procedures][1] to mount my .img file in `/etc/fstab` (for ubuntu mate 20.04 x64)

[Create `.img` file][2]:

```
dd if=/dev/zero of=filename.img bs=1024 count=2M
sudo mkfs.ext4 filename.img
```
Note: also be done with gparted with [this method][3]

**The problem:**

[Mount `/etc/fstab`][4] in `/mount/point`:

```
/home/user/filename.img /home/user/vdisk ext4 defaults 0 0
# or
/home/user/filename.img /home/user/vdisk ext4 loop 0 0
# or
/home/user/filename.img /home/user/vdisk auto loop 0 0
```
But always show 2 units: vdisk (mount) and loop (not mount) (see image)

[![enter image description here][5]][5]

if i try to click on this other drive showing unmounted i get the following message:

[![enter image description here][6]][6]

Why doesn't it just show the fileimage.img image mounted in the vdisk folder?

if I run any of the following commands:

```
sudo mount -a
# or
sudo mount /home/user/vdisk
```

The same thing that I describe in my post appears.

My fstab (I have altered the UUID for security reasons):

```
# / was on /dev/sda2 during installation
UUID=9f92d1aa-458d-441a-b349-abcdefghijkl / ext4 errors=remount-ro 0 1
# /boot/efi was on /dev/sda1 during installation
UUID=F798-ABCD /boot/efi vfat umask=0077 0 1
/swapfile none swap sw 0 0
/home/user/filename.img /home/user/vdisk ext4 defaults 0 0
```

List:
```
sudo losetup --list | grep filename.img
/dev/loop8 0 0 1 0 /home/user/filename.img 0 512
```

But, if I remove the `/etc/fstab` line, delete `/dev/loop8` and mount `.img` image manually (with the followings commands), the described error does not appear

```
sudo mount -o loop /home/user/filename.img /home/user/disk
# or
sudo mount -t ext4 -o loop /home/user/filename.img /home/user/disk
```

**Workaround:**

mount `.img` manually to `/dev/loopXX` available:

```
losetup -f
/dev/loop8
sudo losetup -P /dev/loop8 filename.img
sudo losetup -l
/dev/loop8 0 0 0 0 /home/user/filename.img 0 512
```
edit `/etc/fstab` and put the line:
```
# /path/to/loop/device /path/to/mount/point auto loop 0 0
# example:
/dev/loop8 /home/user/disk ext4 defaults 0 0
```
and:
`sudo mount -a`

But this method is not permanent and i should do what it explain in [this post][7]. But I consider that if all those steps are necessary to make a permanent loop, it is better not to use `fstab` and replace it with bash script that mounts `.img` and program it in the `crontab`.

**Summary:**
- There is no error
- The image is mounted (manually and with fstab)

**About mount:**

When mounting the `.img` in `fstab`, it appears **duplicated** (one is mounted and the other is not). This does not happen when mounting the `.img` manually or `/dev/loopXX` in `fstab`

Only Ubuntu Mate 20.04.3

This appears to be a bug in Ubuntu Mate 20.04.3. In Ubuntu version 20.04.3 this problem is not present

[![enter image description here][8]][8]

Link: https://unix.stackexchange.com/questions/670369/what-is-the-correct-way-to-mount-an-img-in-fstab

  [1]: https://unixcop.com/how-to-create-a-virtual-hard-disk-in-ubuntu/
  [2]: https://unix.stackexchange.com/a/182938/266428
  [3]: https://askubuntu.com/a/672860/828892
  [4]: https://unix.stackexchange.com/a/326537/266428
  [5]: https://i.stack.imgur.com/Zfkow.png
  [6]: https://i.stack.imgur.com/cdIEU.png
  [7]: https://askubuntu.com/a/81225/828892
  [8]: https://i.stack.imgur.com/DqvEB.png