SUMMARY
I’m trying to keep my photos 100% unmodified/original, ie. I want the file hash to never change, any any edits, tags, gps data or whatever should be saved to xmp sidecar files.

Now I’m trying to rotate photos in the thumbnail view, but no matter how I configure the metadata settings, it seems to either only save the rotation settings to the database, or to both the image metadata and the xmp sidecar.

Settings/Metadata/Sidecars
“Write to sidecar files” is set to “Write to XMP sidecar only”

    Settings/Metadata/Rotation - “Write flag to metadata if possible” ← checked
    This causes the rotation data to be written to both the image itself, and to the xmp sidecar.

    Settings/Metadata/Rotation - “Write flag to metadata if possible” ← unchecked
    This causes the rotation data to be written only to the database, not to the image metadata or to the xmp sidecar.

What I want is that the rotation data is only written to the xmp sidecar (and the database, or not, dosen’t really matter), but not to the image metadata to keep the files 100% original.

This feels like bug in that the "Write to XMP sidecar only" setting is not fully honored since rotation data is written do the image metadata as well.

STEPS TO REPRODUCE
1. Configure Settings/Metadata/Sidecars so that “Write to sidecar files” is set to “Write to XMP sidecar only”
2. Rotate an image in the thumbnail view.

OBSERVED RESULT
The rotation metadata is written to *both* xmp sidecar and image metadata.

EXPECTED RESULT
Rotation metadata should only be written to xmp sidecar.

SOFTWARE/OS VERSIONS
Linux: Debian 13 with digiKam 9.0.0 installed from Flathub.