Invert order of `CodeMirror.multiplexingMode` arguments so that double dollars are no longer interpreted as an opening single dollar followed by a closing single dollar.
Invert order of `CodeMirror.multiplexingMode` arguments so that
double dollars are no longer interpreted as an opening single dollar
followed by a closing single dollar.

jupyter/jupyterlab,jupyter/jupyterlab,jupyter/jupyterlab,jupyter/jupyterlab,jupyter/jupyterlab