Braket Notation doesn't work on Math Preview

[AnimeshSinha1309]

Issue Description
Math Statement Preview does not work with symbols added from external packages, eg. Braket.

To Reproduce
Just write out a LaTaX document that has \usepackage{braket} and in the document $\braket{val | operator}$ and hover over the Equation to see the Predicted Math output.

Expected behavior
The Braket notation should be converted to the way its displayed in LaTeX, as <val | operator>, in the preview.

Sample TeX file

\documentclass{article}

\usepackage{amsmath}
\usepackage{braket}

\begin{document}

\section{This is the Notation}
$ \braket{ val | operation } $

\end{document}

[tamuratak]

Duplicate of #914.

[AnimeshSinha1309]

Supporting packages in general may seem to be difficult, but the Bra-Ket notation seems to be common enough in the field of Physics and Math that it seems worth implementing it in the Preview. Also, I am a new developer, so can I take an attempt at fixing this?

[James-Yu]

@AnimeshSinha1309 The preview heavily relies on mathJax, so that repo seems to be a better place for feature request. Contributions to the public domain are always welcomed by everyone.

[AnimeshSinha1309]

MathJax - Add extension for LaTeX package braket #2029 may make it to the next release, hope we can try after it does make it to an official stable release?