the NoScript extention, then you have to tell it to allow scripting for the website you are on.
Hope this helps.
Rick
I'm having problems opening links to .swf files in firefox. I'm running the most current version, have uninstalled it, restarted and installed again with no luck.
When I click a link to a URL ending in .swf I get the download prompt pop up asking me to open/save etc, rather than to just view it in firefox. This happened suddenly for no reason I could think of as nothing had been installed or uninstalled. I can view embedded flash without any problems or in IE. Any ideas?

Chowhound
Comic Vine
GameFAQs
GameSpot
Giant Bomb
TechRepublic