Use the graynotes option to specify whether or not comments, remarks, replies and placholders should be emitted to the output document.
Syntax
Graynotes are normally not written to the output document, but this can be changed using the graynotes option. When enabled, graynotes will appear in the output document using HTML comment tags.
Placeholders can be emitted as hidden comments or as visible text. Use the placeholders option to specify how they should be emitted.
Placeholders
When the placeholders option is graynote, the content of the placeholder will be emitted using HTML comment syntax.
When the placeholders option is text, the content of the placeholder will be visible in the output document as regular text.
When the placeholders option is none, the content of the placeholder will be completely omitted from the output.
When the placeholders option is auto and the graynotes option is specified, the content will be emitted using HTML comment syntax. When the placeholders option is auto and the nograynotes option is specified, the content of the placeholder will be completely omitted from the output.