When you edit [[Wikipedia:Help desk]], you get the custom editnotice [[MediaWiki:Editnotice-4-Help desk]]. The editnotice is emitted inside a table, between <td> and </td>. The editnotice contains a bulleted list, rendered as <ul> with a bunch of <li>'s. However, for some reason, the last </li> and </ul> come out *after* the closing </td>, making them orphans, so to speak. I don't know if this affects other custom editnotices.