I've noticed that Prince, while supporting RGB and CMYK images, will strip out their embedded ICC profiles during rendering, which causes me some issues when I later try to preflight the generated files as PDF/X-3. Are their any plans to support ICC profiles in images in the future?

Yes, we will need to do this. Which image formats are you using?

We're currently using JPEGs.

JPEG images should be embedded in the PDF file exactly as-is, so technically the ICC profile is still there. But presumably we need to extract it and duplicate it in some Adobe-friendly manner within the PDF file.

I’m appalled! There’s nothing else to say.

At the lack of support for ICC profiles? We can expedite this feature if it is important to you.

This would be very important feature to ensure the PDF is ready for the printing house, awesome if this could be prioritised.

We have fixed this in the latest Prince alpha, which embeds image ICC profiles in the PDF.

Prince 10 is now available, and includes ICC profile support for images.