Why doesn't this page work with Mate?

["John J. Boyer" <john.boyer@abilitiessoft.org>]

Hello,

Please look at the attached html fille. It is a small experimental page.
 It works with Chrome on Windows, but not with Chromium or firefox on mate. 
 Why is this? Can I make it work? It will be used to develop a word-association O
 game for my websites.

Thanks,
John

-- 
John J. Boyer
Email: john.boyer@abilitiessoft.org
website: http://www.abilitiessoft.org
Status: Company dissolved but website and email addresses  live.
Location: Madison, Wisconsin, USA
Mission: developing assistive technology software and providing STEM services 
        that are available at no cost