ghost pixels arent too common of a bug but they have happened enough to where most of the community is aware of them, the way to get rid of them is to colorpick a normal color and draw over them (which can be a bit annoying since yknow, you cant see them.)

Description: John sprite sheet version 2 Drawn by Scott. (Non-john sprites on this sprite sheet probably made by John) predicted edits made by John (allegedly)