If KaTeX encounters an error (invalid or unsupported LaTeX) and
hasn't been set to
false, then it will throw an exception of type
ParseError. The message in this error includes some of the LaTeX
source code, so needs to be escaped if you want to render it to HTML.
In particular, you should convert
> characters to
> (e.g., using
before including either LaTeX source code or exception messages in your
HTML/DOM. (Failure to escape in this way makes a
attack possible if your LaTeX source is untrusted.)
Alternatively, you can set
false to use built-in behavior
of rendering the LaTeX source code with hover text stating the error.