Strange corruption

Trying to understand what’s going on here. I’m getting a corrupted preview of the image I’m working on. It looked fine, then I restarted darktable and after that it looked like this. I have enabled and disabled every module. Nothing works.

If I press “original” in duplicate manager the duplicate looks fine.

I have masked the thumbnail strip and the second duplicate for privacy reasons.

Did you try to disable OpenCL?

What kind of noise reduction did you use?

Tried now and restarted. Same thing.

Generic poissonian. Same thing if I disable denoise module.

If you paste that history stack on another image does it go like that…