idk but this makes things better

src/lib/ui/Canvas.hx

@@ -67,7 +67,7 @@ class CanvasKeyValueIterator{
 	}
 
 	public function hasNext():Bool{
-		return index.y < canvas.length && index.x < canvas[index.y].length;
+		return index.y < canvas.length && index.x <= canvas[index.y].length;
 	}
 
 	public function next():{key:Vec2<Int>, value:Pixel}{