blue blotches when switching on color zones

Hi, I am using dt 2.4.3 for windows and I have a problem with the filter color zones: when I activate it, blue blotches appear where there is pure black or dark grey


These blotches are not just some kind of indicator of underexposed areas because they are also present in the exported image. Is this a bug? How can I make the blotches disappear?
Thanks in advance for the help
b

What happens, if you turn off the OpenCL support?

Thanks, apparetly that was it. OpenCL appares to have an effect on many things…

maybe you had the exposure warnings enabled and the areas become highly underexposed?

I’ve had similar problems - black blotches in highlights - on a Windows 10 laptop with a plain Intel GPU, that can’t do a lot anyway. It was usually much more noticeable in combination with colour zones.

On the same laptop, running Ubuntu, OpenCL isn’t available.