test-repo/changelog_unreleased/markdown/19878.md

Strip blockquote markers from a setext heading's continuation lines (#19878 by @Kjubikstronk)

A setext heading spanning multiple lines inside a blockquote kept the > marker of its continuation lines as literal text.

<!-- Input -->
> Multi
> Line
> ===

<!-- Prettier stable -->
> Multi > Line
> ===

<!-- Prettier main -->
> Multi
> Line
> ===