Keep the text, tidy the layout
Formatting uses Prettier with Markdown parsing. The side-by-side source and result let you inspect list markers, wrapping and fences before copying. Prose wrapping is preserved by default.
A worked example
A heading, a list and a fenced JSON block stay separate blocks. The code inside the fence may be formatted according to its named language. To check the JSON inside a fence on its own, use the JSON formatter.
Before you use the result
Formatting cannot tell whether your renderer supports a particular extension. HTML inside Markdown is treated as markup text here and is never executed. Review the visible line comparison for changes.