It's coded so that we only have to check if it works in Firefox. It's not like we're explicitly trying to leverage Firefox-only markup or CSS. I believe the idea is to reduce waste of development time and effort. I think I'm going to call YAGNI at this point re: future patent problems. I don't see that happening soon, and I'd gladly take the time savings now, and cross that bridge when we get to it -- if it comes at all.