Colormanagement features not supported?

I've just received this exact message in the latest version as well (25.1.0 B.73) but I've been editing in this project for weeks and haven't used any beta version at all. This was the first time I've received this message.

I added the Lighting Effects to a clip and have since been unable to save. I found a way to comfortably save, close Premiere and reopen it -- that's when I received this message. Nothing seems different in the timeline or within any of the clips, though, so I'm confused why I'm getting the message, especially after reading it usually comes from using a beta version.

I had the same problem. I found the solution.
1) Open the project in premiere pro (usual version, not beta)
2) Pres "open project in this version"
3) Create new sequence
4) Copy all elements from old sequence to new sequence
5) Delete old sequence created in beta
6) Seve project

I've seen it too. Like Kevin says, it's from using the Beta, and going back to the release version.