I'm having an odd issue with the halftone filter that has cropped up. I'm currently working on some comic creation tutorials using Krita, but when I apply the halftone filter to an area of grey there are dot density issues on irregular edges. The pattern appears as it should in the general area of the selection, but edges have blobs of black and multiple dots clustered together. Any idea what might be happening?

No solution, but I've found a workaround. The issue seems to be related alpha transparency. If I fill the layer with white, then draw or fill selections in that layer, the halftone filter works as you'd expect it to. If the colour to be converted is on a transparent background, anything touching the transparent area seems to confound the filter.

Maybe show us a screenshot of this issue? Otherwise it's hard to even explain why it happens, not only fix

This has been happening since version 3.3.3 and possibly earlier but I didn't look at earlier versions.
Version 4.2.0 introduced additional artifacts, related to the content bounding box, which become part of the image.
Both problems are present in the latest Nightly build.

As noted by nvision, these problems only happen if the content is on a transparent background and there is a simple workaround.
The workaround may not be suitable for everyone though.

I assume that not many people use the Halftone filter if this hasn't been noticed before.

@nvision: You can raise a bug report here: https://bugs.kde.org/
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