aligned / align* environments not working
When I run this test document (.adoc attachment) through 'npx asciidoctor index.adoc' I get the desired math rendering (HTML attachment). But running it through 'npx asciidoctor -r @djencks/asciidoctor-mathjax index.adoc -o index-asciidoctor-mathjax.html' gives me a black background with 'Unknown environment 'aligned'' text in it.
The 'aligned' (and similar 'align*') environments are definitely supported by MathJax 3.2 AFAICT from their website. I don't know if something about the frontend configuration could cause this? align* comes from the amsmath package in actual LaTeX though I'm unsure about aligned. Perhaps mathjax is being setup by the extension in a way which doesn't enable some of this functionality? Otherwise I'm without a clue.
Running what I think are current versions of these components:
$ npm list asciidoctor @djencks/asciidoctor-mathjax mathjax-full
docs-site@ /home/tree/git/antora/antora/docs-site
├─┬ @djencks/asciidoctor-mathjax@0.0.8
│ └── mathjax-full@3.2.2 deduped
├── asciidoctor@2.2.6
└── mathjax-full@3.2.2