Never mind - ignore me; I'm running the NoScript plugin and although I'd allowed for duckduckgo I'd not done so for yahoo.

Might want to add a noscript javascript required warning though :)

Ahh, thanks for the clarification. Is there a way to display a warning to just noscript users?

I have no idea, but the <noscript> tag will show to anyone with JS disabled.

http://www.w3schools.com/tags/tag_noscript.asp