I just updated to Premiere Pro 2025 and migrated a project I've been working on (using MacOS Sonoma 14.6.1). I'm using proxy files and noticed that when I render my sequence (or switch to view native files) the colour is different.
I wonder if this has something to do with some auto colour management feature as my native files are MXF (Canon) and proxy files are Pro res 422 MOV files.
You can see in the screenshots that the proxy file has more contrast to the native. These are ungraded clips. Once graded the discrepancy is even more noticeable.
I have made sure my sequence is set to rec 709 and I have overridden any colour space on the clip to rec 709 but the problem persists. I have toggled on and off the various settings that could causes this like "display colour management" "auto detect log video colour space" "auto tone map media" with no luck.