JSmol-MathJax Compatibility Test

When $a \ne 0$, there are two solutions to $ax^2 + bx + c = 0$, and they are $$x = {-b \pm \sqrt{b^2-4ac} \over 2a}.$$ The trick here is to start the Jmol loading process only after the MathJax process is complete. We monitor the contents of the MathJax_Message div every 10 ms, and while it doesn't exist or its message contains the word Loading, we loop:
    checkMathJax = function(fReady) {
      return (!$("#MathJax_Message")[0]
        || $('#MathJax_Message:contains("Loading")')[0]
        ? setTimeout(function(){checkMathJax(fReady)},10)
        : fReady());
    }
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