@Greg_S. Thanks for taht information. I did have contact with a friendly indian Adobe-specialist for PSE22. He did not kno about that fault and he did give the issue to another specialist. He should contact me, but I did not hear anything yet.
I also use PSE 2022. The effect you describe only happens on a blank solid color canvas. If I apply an effect to a photo or image, the results are what you would expect. Are you applying an effect to a blank canvas?
The attached screenshot shows the Neon effect applied to a black & white photo.
@Walter_H, although you (and I) can only reproduce this issue with an empty layer, there are now several reports of users having similar problems to the OP. Adobe is aware of the problem and is hopefully working to resolve it. Here is one of the other discussions.