twbs/bootstrap — pull request #15322 by dannguyen (2014-12-08 02:37:27+00:00)
Title: Update scrollspy usage to have height requirement

Not sure if this is a workaround or actual usage, but without explicitly setting the height requirement on the spied-on element, the scrollspy will not work:

http://stackoverflow.com/questions/13134013/how-to-use-bootstrap-scroll-spy