Invalid directory separator on Windows

Is there an existing issue for this?

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

Describe the bug

I have moved a folder arranged as Year/Month/Day between to drives, using a tool outside of darktable.

When I use "update path to files" to reattach my files the folder structure gets the wrong directory separator.

Steps to reproduce

1. Moved a folder using a tool outside of darktable.
   2 Use "update path to files".

Expected behavior

The same separator character in the whole path.

Logfile | Screenshot | Screencast

No response

Commit

No response

Where did you obtain darktable from?

darktable.org / GitHub release

darktable version

5.4.0

What OS are you using?

Windows

What is the version of your OS?

Windows 11

Describe your system

No response

Are you using OpenCL GPU in darktable?

Yes

If yes, what is the GPU card and driver?

Intel Iris

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

No response

Reproduce the issue on Windows 11 by moving a Year/Month/Day folder between drives, then using darktable’s “update path to files” workflow. Trace the path handling involved in that workflow and verify that the resulting path uses one consistent separator throughout.