No, I’m referring to what was say above a few weeks ago and that was forked to this thread: Color management in Siril, need help and refactoring.
So, a Siril problem.
The Astro-TIFF support would simply be copying metadata so that if you do a siril export to TIFF, processing with RT, then reimport from RT to siril, you don’t lose what’s useful for astronomy image processing afterwards.