Strange "gradient"-Like bug?

While I was working on some art using the fill bucket tool my hair seemed to mix with the white to make this weird gradient effect and t appears randomly I can zoom in and it wont be there but sometimes it does and same for zooming out it has no rhyme or reason


I’m assuming this is a bug with art engine being used


Oh yes I’ve had something like this before, this is probably a bug with the fill bucket tool