Meta data export not working correctly in appimage

Is there an existing issue for this?

• I checked and did not find my issue in the already reported ones

Describe the bug

When using the official darktable appimage the export of metadata is not working correctly.
I cull (using the color flag symbols) and rate (star rating) my photos in digiKam.
I import CR3 files into darktable, process the files and export the files as png files.
I view the files in digiKam. The hierarchical keywords and color flag information are missing. Star rating is available.
When I repeat the same process using the .deb of darktable (provided on software.opensuse.org) everything works as expected:
Color flags and hierarchical keywords are exported correctly.
The meta data export settings in the .appimage and the .deb version are the same.
In both cases I use darktable 5.6

Steps to reproduce

Goto Export model
Select image and png format for export
Export image as png
View image and meta data in digiKam

Expected behavior

Export meta data (color flag symbols, hierarchical keywords) independent of the build (.appimage or .deb).

Logfile | Screenshot | Screencast

Above screenshot shows thumbnail in digiKam with correct meta data (color flags, star rating, hierarchical keywords) exported via darktable .deb Above screenshot shows thumbnail in digiKam with missing meta data (color flags, hierarchical keywords) exported via darktable .appimage Above screenshot shows meta data export settings in both versions of darktable .deb and .appimage.

Commit

Where did you obtain darktable from?

distro packaging

darktable version

5.6

What OS are you using?

Linux

What is the version of your OS?

Ubuntu 24.04

Describe your system

X11

Are you using OpenCL GPU in darktable?

Yes

If yes, what is the GPU card and driver?

Please provide additional context if applicable. You can attach files too, but might need to rename to .txt or .zip

No response

First reproduce the export using darktable 5.6 on Ubuntu 24.04 with the official AppImage and the .deb, then compare the PNG metadata in digiKam. Check the AppImage and .deb build or packaging differences affecting metadata export; done means color flags and hierarchical keywords are preserved in both builds.