I was honestly not sure where to post this.. I know there is usually a Bug Report thread for new versions but I couldn't find one since the new updater.
Anyways: I was building a ladder behind a Castle Wall and discovered this glitch.
If you can't tell what's going on, bricks hide their faces when that face is completely covered by other bricks. A brick from the ladder thought it was being covered by the castle wall so it hid itself, but it's actually visible through the window.
Just a relatively minor bug, not sure if it's easy to fix or not.