Ruby on Rails: Action Text to_markdown: <code>/<pre> content escapes its delimiter, letting a stored body inject arbitrary Markdown

Summary ActionText::Contenttomarkdown escapes text nodes so that a stored rich text body cannot turn into Markdown syntax. Text whose immediate parent is or is exempt from that escaping MarkdownConversion::SKIPESCAPINGPARENTS and is instead kept inert by the delimiter its visitor wraps around it...