When I use badges within .nav-tabs, list items with an .active class still have a visible bottom border. This problem only occurs to me when using Firefox on Linux, with Bootstrap 3.3.5 and 3.3.6. Chrome displays it just fine.

Here is a JSBin, and a screenshot of how it looks on my end.

http://jsbin.com/qekubi/1/edit?html,css,output

I fixed it by reducing the padding-top and padding-bottom of the badge by 1px.