Braces in latex get escaped

I’m using a simple template with KaTeX and the following fails:
$$\mathcal I := { X\subset E : \text{the vectors in $X$ are linearly independent} }.$$

I suspect this is due to Hugo automatically replacing { → {, and I check this by testing $a_{b}$.

How can I go around this, so that my LaTeX code also works on other markdown parsers that do not do this replacement?

Going to bump this. To summarize, \{ is being replaced with {, probably due to HTML escaping.

I recently got a contribution to my Zen theme that implements KaTeX. Tested your example and it seems to work just fine. At least it renders the same way as it does on https://katex.org.

If you post a link to your repo we can check what the difference are.