On macOS 15.3.2 color management in the latest (last) version of Photo Mechanic 6, build 7269 thumbnails and previews look flat. This is for JPEG images with embedded sRGB and Adobe RGB (1998) profiles.
Reverted to Photo Mechanic 6 build R7212 and colour is accurate.
I compared the images with Lightroom and Photoshop, both Adobe apps show/read the color profiles correctly.