A strange menu thing shows up for something that appears to be inside the manual airlock, something that is apparently called; Steel Door <DO NOT TRANSLATE>.
Also, there is a similar bug for tiles, except; it shows what the tile is made of.
Steps to Reproduce
Click on a closed manual airlock (not sure if it happens for mechanized ones) that doesn't have any wires or pipes behind it, then, click on it again and the "menu thing" should show up.
This issue has not been confirmed by a developer yet.