While playing puluc sometimes stacked pieces leave gap between each other, as if one of neighbouring pieces was invisible. I suppose that it happens when you capture a pawn of color that is the lowermost one in the stack you are capturing with. E.g. Black captures white, then again this stack captures another white.
On the screenshot below two stacks have this exact issue (the ones towards opponent's side), where it's 3 pieces in each, but visible are only 2 of them, with gap inbetween
On the screenshot below two stacks have this exact issue (the ones towards opponent's side), where it's 3 pieces in each, but visible are only 2 of them, with gap inbetween