Check for rendered HTML before rendering in client

It's OK if you don't want to merge this, but I'm just letting you know of an issue I'm having and my solution.

The issue is client-side rendering on really large pages (e.g. release notes for an app that has had a lot of releases in its history) is slow, and sometimes hangs in Firefox and Safari. 

After each update, I'm now rendering the HTML on the server (not shown here), and preferring it in the client via the edit below.