Why different apparent exposure 'limits' between Linux & Windows version of dt?

It seems priort already did what i wanted to do any found some differences. True ? Or you want to redo it all and see if you encounter the same issue?

yes.

Disable all color management features, installed profiles, night vision mode (dimming AND red shift), and so on, and retry with sRGB all along. I have noticed that people do all sorts of bad profiles by ticking all the boxes in the soft, only to destroy things in subtle ways. Also, my wife had a weird issue on Win10 where the night mode would always restart wheneven a new monitor was hot-plugged, it took me a while to troubleshoot it.

My bet is you calibrated your screen with backlighting below 50 % and asked for an high fixed white point, so your profile is applying a crazy gain to try and match that, except it doesn’t and clip.

Your comment has intrigued me; you may remember that I replied saying I had no specific recollection of having modified the black point. You were correct nonetheless: I DID modify the black point, unintentionally, by creating a preset which was applied (I assume) automatically to every image from my Fuji X-T* cameras:

Am I reading this correct that the preset ‘AH-Fuji-Snow’ will be applied to images from my X-T30 camera (which, indeed, they are)? if so, what about the preset ‘1 stop extra’, or indeed any of the others?

In darkroom I can selected an exposure preset of ‘scene-referred-default’, at which point so many gamut problems disappear, but what prevents this preset (AH-Fuji-Snow) just being automatically applied to the next image from a Fuji camera?

btw, I have edited every Fuji image since January 2021 with this preset. Is there no beginning to this man’s talents…?

(Edit): OK - I can answer the question myself now: I failed to notice the ‘column headings’ in this window (because they were so far above the row for the exposure preset…hmm, human factors design ). so I didn’t see the ‘auto’ column and hence didn’t appreciate what the check marks meant. Fixed now, but I have an awful lot of images to go back and re–edit. I trust a suitable application of history stack copy and paste will work.

Onwards and less downwards, please.

I think your auto presets can be made specific to camera and lens models so you can still use your preset you sound like you just need to go back and tweak it a bit to be more specific…