Alright, just noticed this tonight for the first time. I'm recently and slowly converting to FF as v3 is growing on me. However, I commonly use the 'Right-click > Copy' (or cut and/or paste) options. Just got used to doing so instead of the key short-cuts Ctrl+c (or x or p or whatever).
Now when using the key short-cut method everything is fine and dandy but when using the right-click method you get the following error (which I'll take a sceenshot of right now)....
Notice its a screenshot of me writing this message
ok, the link takes me to this page for an explination and 'fix'... http://www.mozilla.org/editor/midasdemo/securityprefs.html
Well that just seems absurd that that even needs to be done, so if there is something that can fix that 'issue' on the sites end that would be a good idea I think.