Hide the single & coop bosses list, and I think you can hit the World Boss with that problem.
Still, it's odd that it hasn't been fixed yet, and that it only happens to some people.
What we know, it's that it ain't a browser issue, but in Mozilla there's a way to sort of fix it.
Go to the outbreak/boss/whatever screen and right click. My browser's on Spanish, so I can't tell the name of the option, but it's the only one that shows more options, and from those options pick either the second or the third, both worked back when I had that problem.
Last edited: May 16, 2011