ICC color profile being stripped from JPEGs upon submission (but not upload)

This was tested on v0.11.8 (at pixelfed.de).

JPEG images that have an embedded ICC colour profile (for example, every photo developed by Darktable on Linux) have that colour profile stripped away during posting, resulting in wrong colours in my monitor.

If I open the preview image after uploading but before submitting (e.g. while adding alt text), the colours are still correct. It's only after posting that they get wack. So whatever processing is done post-submission must be deleting the colour information.

Here's a test image with profile information, and it renders with correct colours in my monitor on Firefox and other image viewers I tried:

and this is a screenshot of how it shows in my monitor if I strip away the ICC colour profile from the EXIF:

Left side (with profile) is how it shows on most apps for me, right side (without profile) how it appears in Pixelfed post-submit.

For reference, this issue doesn't affect the same JPEG if I upload it on Mastodon or other social media, because the colour profile is preserved.