Can't change comp resolution

As you can see in the video, I can't change the resolution of my composition. No matter what I select, it always stays at full res. I'm seeing this in all projects since updating to 25.x – not sure if it's unique to 25.5.

Has anyone seen this behavior?

 

Bug? User/config error?

 

AE 25.5.0 (Build 4) on Mac OS 26.0