activeadmin/activeadmin — pull request #3690 by ksylvest (2014-12-11 06:04:51+00:00)
Title: Fixing Style of Dropdown and Tabs For Both First and Last Item Entries

Pretty minor style bug for these components when they are both the first and last child (i.e. a single tab). Without the fix a single tab would have rounded borders on only one side.