I guess I missed this stuff in the release notes. Notably, headings are now marked off with hash tags (# heading) like markdown. I noticed this when my Go formatter automatically detected it and forced it to be there. Apparently, this was added in 1.19.
Also, indentation can be a single tab instead of four spaces as before.
And I love that clean reference links have been added:
Here is [skilstak] link.
[skilstak]: https://skilstak.io