Seams to only be doing this if the tab is being output by something else already. Specifically this impacts CB Quickstart since that tab is being embedded into the About tab. Unpublishing the about tab fixes the issue. Doesn't seam to be a template problem but likely some sort of bug in CB that has been there for a long time now, but CB Quickstart revealed it. Have added a bug ticket to fix. For now I don't recommend outputting a tab in 2 different locations at once on profile. In the above case for example once About, which is outputting that tab inline, is unpublished the issue fixes.
forge.joomlapolis.com/issues/7967