LaTeX block math works when the block is standalone, but not in a tight list; i.e.

- test 123 \[ f(\mathbf{a} + \mathbf{h}) - f(\mathbf{a}) = \sum_{k - 1}^{n} A_k h_k + || \mathbf{h} || \mu(\mathbf{h}) \]

Will lead to class=katex, where it should lead to class=katex-display. This is an issue, since having to add newlines around block math breaks the pattern of adding block math into lists.

From my understanding, this might be an issue with the Passthrough extension, as it looks like it only processes paragraphs when looking for inline to be transformed into blocks and not other containers. I've created a PR for this: #39

$ hugo version
hugo v0.152.2+extended+withdeploy linux/amd64 BuildDate=unknown