Retrieving the full HTML from AngleSharp, including the Doctype

AngleSharp is a pretty sweet document parser for .NET. I was parsing some HTML and making some modifications. All good. Then retrieving the full, modified HTML at the end had me stuck. All the examples I could see said to do it like this: document.DocumentElement.OuterHtml. This worked, except it was missing the Doctype. The correct way to do it is to add a reference to AngleSharp.Extensions and then you get a nice extension .ToHtml(), which is perfect.

I did find this in the docs after I dug into the source code, it is under Getting Single Elements in the examples section. Which makes no sense to me but hey, I guess I was just having one of those days.