System picture deleted by saving again

[itkfm]

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• [x] I have read the contributing guide lines at https://github.com/opnsense/core/blob/master/CONTRIBUTING.md
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Describe the bug

After setting a Picture in System › Settings › General and saving the picture is set as expected. But saving that page again (with no change to the picture) deletes the picture.

To Reproduce

Steps to reproduce the behavior:

1. Goto System › Settings › General.
2. Click on the picture selector and upload a picture by pressing [Save].
3. The settings page confirms the changes and shows the uploaded picture.
4. Press [Save] again.
5. The settings page confirms the changes and the previously uploaded picture is gone.

Expected behavior

The uploaded picture stays in place.

Describe alternatives you considered

Not using the new Picture widget.

Screenshots

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Relevant log files

n/a

Additional context

n/a

Environment

• OPNsense 24.7.5_3-amd64
• Firefox 131.0 on GNU/Linux
• Chromium 129.0.6668.70
• Picture is a PNG-8 file.

[itkfm]

Picture is a PNG-8 file.

Also tested it with JPEG – The one in the screenshots is a JPG file.