[WARNING] Could not parse YAML metadata at line 9 column 1: :2:12: Expected start of line
[WARNING] This document format requires a nonempty <title> element.
  Please specify either 'title' or 'pagetitle' in the metadata,
  e.g. by using --metadata pagetitle="..." on the command line.
  Falling back to 'article'
[WARNING] This document format requires a nonempty <title> element.
  Please specify either 'title' or 'pagetitle' in the metadata,
  e.g. by using --metadata pagetitle="..." on the command line.
  Falling back to 'article'