Haze removal works but doesn't export in Win10

Haze removal works great. I can see still its effect when I move the file back to light table but when i export the image the effect is missing. Other edits are fine. Anyone else run into this?

Can you provide RAW file +xmp on which problem can be reproduced reliably? Is the issue present only on Win10? (if you can’t test this-no problem, just provide RAW+xmp please). Do you have OpenCL enabled? Which version of darktable are you running on?

Thank you for your speedy reply. I tried it again today and it worked. I’ll try a few more times to be certain. Most likely, operator error I think!