Unknown image format/type

[RosaDeSa]

Version of Singularity:

What version of Singularity are you using? Run:

singularity-ce version 4.0.3

Expected behavior

I'm trying to pull a docker container with singularity in a nextflow pipeline. After updating singularity to version 4.0.2 I'm having issues in pulling the container.

Actual behavior

Command error:
ERROR: Unknown image format/type: /home/users/scratch/work/singularity/staphb-seqtk.img

In the singularity cachedir, I found the container with the .img extension, but it seems singularity doesn't recognize it. Maybe it is looking for a simg extension?
If I move in the singularity directory and run singularity shell or singularity exec on the img the container works perfectly.

Steps to reproduce this behavior

docker container that I'm trying to pull in the pipeline is the following: docker://staphb/seqtk:1.3

What OS/distro are you running

PRETTY_NAME="Debian GNU/Linux 11 (bullseye)"
NAME="Debian GNU/Linux"
VERSION_ID="11"
VERSION="11 (bullseye)"
VERSION_CODENAME=bullseye
ID=debian
HOME_URL="https://www.debian.org/"
SUPPORT_URL="https://www.debian.org/support"
BUG_REPORT_URL="https://bugs.debian.org/"

How did you install Singularity

Singularity was installed on HPC.

[github-actions]

New issues are no longer accepted in this repository. If singularity --version says singularity-ce, submit instead to https://github.com/sylabs/singularity, otherwise submit to https://github.com/apptainer/apptainer.