[azakai]

Mozilla is a nonprofit whose goal is to promote the web. So it is very important that this runs well on Firefox, Chrome, and on all other modern browsers - if it didn't, this would be pointless for Mozilla to do.

Mozilla helped out here, but the goal is to show that games on the web can be fun, and of course that means anywhere the web can run, in any browser.

edit: the distinction is also noticeable in that this is the Humble Mozilla Bundle, and not Humble Firefox Bundle.