Sets the CSS clear property, which forces this float underneath the side specified with this attribute. So, clear=left (which is the default) will place the element after all the left floating elements before it. Options are left, right, both, or none.
Set the CSS width.
Limits the depth of subheadings shown. For instance using limit=4 will hide the fourth level and deeper subheadings in the hierarchy. And limit=2 will hide all subheadings leaving only the main headings. This is implemented as a CSS class in the MediaWiki:Common.css.