It is not unusual for the original text to be visible before MathJax processes it. If MathJax needs to load any components (like its output jax the first time it is used), that is done asynchronously, so the page will be displayed in the meantime until the component is loaded.
You could set the div's visibility:hidden property before loading its contents, and then after it is loaded, typeset the math setting visibility to "" afterward. You would need to use the MathJax.Hub.Queue to synchronize that.
It is not unusual for the original text to be visible before MathJax processes it. If MathJax needs to load any components (like its output jax the first time it is used), that is done asynchronously, so the page will be displayed in the meantime until the component is loaded.
You could set the div's
visibility:hiddenproperty before loading its contents, and then after it is loaded, typeset the math settingvisibilityto "" afterward. You would need to use theMathJax.Hub.Queueto synchronize that.