I lost the project this bug originally occurred on, but I was able to reproduce it. I tried both loading old projects and creating new 64x64 projects. In all cases, regardless of the Center’s placement the bug was present. I’ve tried zoom levels from x1 all the way to x50, the bug persists regardless of the used zoom level. The Dots counts I’ve tried were 2 and 4, both of which had pretty much the same issues.
I’ve accidentally found a different variation of this bug while playing with it in a temporary project, I don’t know what triggered this behavior, because it only happens within the said project:
The pixel previews are not offsetting anymore, i.e. moving the mouse near the borders does not cause one pixel to move while the other stays, but the borders themselves are distorted and don’t line up with the pixel previews:
This is very hard to put into words, but attempting to draw while the mouse cursor is out of the pixel preview causes some pixels to be drawn in the place of their pixel previews, and some pixels choose to be drawn in place of the mouse instead, e.g.:
I’m guessing what happens above is, the pixel preview instead of glitching while the cursor gets near the border, somehow has an offset off said border instead. It’s worth mentioning that the distance the mouse cursor is able to travel outside the pixel preview varies both horizontally and vertically depending on where the mouse is. I haven’t noticed a consistent rule dictating how far it can go, but it seems like the offset is always the same for the same pixels, regardless of the zoom level as well.
Preview of the varying offsets:
Preview of the offset not changing for the same pixels regardless of zoom level:
I hope this will help in tracking the problem. Here’s the project file I’ve been using for the previews on the “second variation” of the bug:
Side note: the issues appear in the exact same way after closing & reopening PM or closing & reloading the project file.