Thanks for looking into this and merging the patch.

Bug reproduced on image 2026.07.21-1151-rolling and proposed patch tested.

https://github.com/vyos/vyos-1x/pull/5358

Forgot to mention that lacking proper FS trimming has a very negative impact when running VyOS virtualised and having the filesystem sitting on a thin provisioned volume, like for instance LVM thin. The absence of discard commands coming from the virtual node does not allow the cleaning of unused blocks.