Color adjustments not showing in program

I'm new to Premiere, but so far haven't had trouble doing color grading and adding effects to clips. Starting today though, I have a problem: program monitor doesn't show color adjustment changes. When I adjust exposure slider for example, I see the sequence thumbnail getting lighter and darker, but not the program view. I'm not using adjustment layers. I can easily reproduce this, creating a new project, importing a clip, creating new sequence from clip, and adjust color. Same with adding effects.

I'm on a Macbook Pro in clamshell mode, using external display connected with HDMI; not using multiple monitors via preferences: playback (no video device checked there).

2.8 GHz Intel Core i7

1tb SSD

16gb ram

MacOS 10.12.5

Premiere 2017.1.2

Screenshots show exposure change, visible in sequence thumbnail (bottom left), but not program (main window).