"umount" error after updating Jail to latest patch level

[Mannekino]

I just tried updating two of my Jails to the latest patch level. However at the end of the proces I'm getting this error. After updating the first Jail I decided to stop all the Jail and do a reboot of my FreeNAS server to see if that fixed the issue. However I got the same error when updating a second Jail.

Should this be cause for concern? How can I prevent this for updating the next Jails.

Code:

Installing updates... done.
umount: unmount of /mnt/system/iocage/jails/radarr2/root/dev failed: Device busy
release: 11.4-RELEASE-p4 -> 11.4-RELEASE-p6
Updated jail successfully.
  + Removing jail process FAILED:
jail: ioc-radarr2: mount.fdescfs: /mnt/system/iocage/jails/radarr2/root/dev/fd: not a mount point

Edit
I updated some more Jails and strangely it doesn't happen every time.

 

[Mannekino]

Just an update that I've since upgraded to TrueNAS 12.0-U1 including upgrading all my Jail to the 12.2-RELEASE at the latest patch level and I haven't encountered this issue again.

 

[emk2203]

It pops up again now for me, running TrueNAS 13.0-U3.1.

Annoying.