[derefr]

In this case, though, the resulting page without Javascript would probably be entirely empty. Maybe Firefox could detect that and throw up a full-page-error kind of thing (like e.g. an SSL cert-failure error page) rather than a dialog. "There's nothing here. We detect <script> tags on the page, so you probably need to [enable Javascript]. Don't do this if you don't trust the site, though—you disabled Javascript for a reason!"

Basically, a heuristic browser-chrome view in place of what used to be a site-author's <noscript> view.