It turns out that MathJax sets cookies to remember your preferences. Specifically, the mjx.menu
cookie. I looked around for hints as how to disable this cookie in the configuration, but found none, so here is my solution:
When creating the configuration element, simply replace the MathJax.HTML.Cookie.Set
function with a function that does nothing.
var conf = document.createElement ("script");
conf.type="text/x-mathjax-config";
conf.text = (
"MathJax.HTML.Cookie.Set = function(){};" +
//...other configuration code...
);
document.body.appendChild (conf);