That webpage looks fine to me - I can see the cards shuffling, as long as Javascript is enabled in Firefox (and allowed in NoScript for all the domains that "feed" that web page).

Beyond making sure Javascript is enabled, see if this helps you.
https://support.mozilla.com/en-US/kb/Websites%20look%20wrong

As far as Report Broken Web Site goes, that was a Mozilla "Web Evangelism" project where Mozilla reps would "reach out" to web sites to encourage them to fix their web sites to conform with established standards. After doing that for the last 5 or 6 years, Mozilla has decided to discontinue that project. That menu item (feature) is gone from Firefox 4.0 betas for many months now.
I am only guessing, but the server that collected the data that Firefox users would submit may have been shut down already, or maybe it just wasn't accessible when you tried to submit that report.

Yes, when I told noscript to "allow all this page" that fixed the display. My bad, as they say. I should have thought of that.

The problem that I was reporting was the inability to report that site, even if I was in error. Your explanation of the end of "Web Evangelism" seems like a good guess, too. I will no longer report unfriendly pages - they are VERY rare anymore anyway.

Thank you very much for the responses.

All well and good...discontinued functionality. Then (like the soon-to-be-discontinued Sidewiki tool) remove those options from the FF 3.6(+) toolbars!!

Some of us are still in the 3.6 generation while we wait for FF to support what we now have (to wit, Google toolbar, etc.). You do us a disservice by implying we can spend time reporting errors, etc., when we can't.

Respectfully but critically,

Webistrator in CO