Do we allow JavaScript to be used on project home pages?

Yes, it is allowed to use JavaScript in the project home page or any domain page. JavaScript referenced from the <HEAD> of a document will not work unless the "Preserve HTML head content" is enabled in the domain and the project (in the Edit project page) JavaScript can be referenced in the body of a document (e.g. a JavaScript hack can be used to hide default items in the left navigation, to reference an external RSS aggregator, etc.).