Repro: ```clojure (markdown.core/md-to-html-string "foo_bar_baz") ;;=> "foobarbaz" ``` Expected: ```clojure (markdown.core/md-to-html-string "foo_bar_baz") ;;=> "foo_bar_baz" ``` For reference, see [this commonmark.js dingus](https://spec.commonmark.org/dingus/?text=foo_bar_baz).