Viewer colors brighter when paused vs playing. Which is correct?

Possibly an old question, but I've noticed that the image in my composition viewer is brighter when playback is stopped than when preview is running. So if I stop playback and apply a color adjustment to a specific frame, and then play, the view is darker than I'd intended.

My basic question is, am I using it wrong? Is the color "correct" when playback is stopped, or "correct" only when playing?

I'm working with color management on in 32bpc and simulating Rec.709 output (I'm on a P3 display). It's possible to screen-grab the difference (see attached), but that doesn't tell me which color is right...