Some recent StackExchanges are starting to include site specific 3rd party JavaScripts - for example, cstheory.stackexchange.com (and math.stackexchange.com) both use what I think is MathJax to render the mathematics. Users of these sites depend on features provided by these "SE plugins", so I'd like to replicate the functionality in SixToEight.

Alas, including MathJax in every site is expensive - the processing it does can be quite intensive, and the poor old iPhone 3G can hardly cope at the best of times. I'd like to include the needed JavaScript only on StackExchanges that use it, but I can't find a way of identifying these sites (short of hard-coding a list, or nasty analysis of the live HTML).

This problem boils down to two questions.

1. Are there other "plugins" used by other StackExchanges that I'm not aware of, that change the content display in a significant way?
2. Is it worth adding a list of these "plugins" to StackAuth, so we can include them only when necessary (and, if needed, disable Stack Exchanges with content we cannot support)?

With MathJax, it's not strictly necessary to have the plugin to view the content - the ASCII content is reasonably readable. It's just significantly suboptimal, and I'm worried that future sites will have other content that really is broken without 3rd party JavaScript.