force the jquery-ui sortable plugin to be larger than its content
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I am using the jquery soortable plugin to create a dashboard. 
When the user drags a widget they have to move it over existing widgets in the sortable to be able to drop it. I want the user to be able to just drag the widget below the existing items and be able to append. However the sortable plugin is always as tall as the items that are inside it.
Is the a way to force the jquery-ui sortable plugin to be larger than its content?
