This issue is apparent on many admin screens: .generalbox is used as the general content container, and then on occasion there are child elements that also have .generalbox assigned to them. We should really have a class for the concept container of all content in the central column, or else we should enforce the use of #region-main for that purpose. .generalbox should not be recruited for that purpose.

Either expand the role="main" container div with a classname so it can take the place of .generalbox as a container of all content in the central column,

  <div role="main" class="maincontent">

or, enforce the use of #region-main for that purpose.