Keep user documentation in a single tab

The 2013b release documentation browser shows a behavior I haven't before. When I view the documentation for a builtin function (such as "sin") and press one of the "See also" links, the next documentation page appears in the same tab. However, if I view the documentation for one of my own functions and click on a "See also" link, the selected documentation is displayed in a new tab. I like tabs as much as the next person, but the number of tabs quickly becomes overwhelming.

Is there a way to turn this behavior off?