ironed

Ohhh... ICC Profiles with low Gamma (i.e. 1, i.e. linear) are (only) available for RGB 32 bit/HDR mode....

the (special, see below: sRGBLin) ICC profile is not shown in Affinity Photo/ can't be chosen (profile is installed properly in C:\Windows\System32\spool\drivers\color). The profile was created in Photoshop (it contains sRGB primaries but has linear TRC, i.e. gamma=1). When an image with this profile embedded/attached is opened in Affinity everything is working as expected. sRGBLin.icc