For me, with a maximized Firefox window in Ubuntu on my 1680x1050 laptop, the page is just exactly the right length that when I get to the bottom of the page the subnav becomes sticky, and it's got margin bugs whereby it doesn't fill up the space where it was (surely Bootstrap got that right? Apparently not), which shortens the page length, causing it to come unsticky again... end result: I can't access the summary row at the bottom of the table.