Post History

## Render MathJax faster
Whether we decide to allow direct use of the `<math>` tag in posts or not, we should use MathML behind the scenes so that posts containing MathJax render quickly even on a slow connection, rather than having to wait for JavaScript to load and run. This will also allow users with JavaScript disabled to view posts containing MathJax.

## No difference for authors and editors
The user experience when writing MathJax will be the same as currently. Editing an existing post containing MathJax (whether written before or after we start using MathML in the background) will still involve writing MathJax rather than MathML. Users who want to continue writing and editing MathJax will see no difference during editing. The only difference visible to users will be the faster rendering[^1].

## No need to see or even know about MathML
Users writing MathJax will never need to see the MathML that is used in the background, in the same way that users writing Markdown never need to see the HTML that is used in the background.


[^1]: All posts created or edited after the introduction of MathML will render faster and be visible even to users with JavaScript disabled. Posts last edited before the introduction of MathML will still render more slowly (the current speed), until they are next edited. We could optionally also discuss running an automated update of all old MathJax posts to use the new faster rendering (they would look identical other than rendering faster) but I'd like to see this change whether it includes old posts or not.