message: Update the comments in Markdown.js
  so they don't claim it;s a wrapper around marked when it's now
  commonmark, and comment why we render markdown to plaintext which
  is somewhat unintuitive.
diff: @@ -17,7 +17,7 @@ limitations under the License.
  import commonmark from 'commonmark';
  /**
  - * Class that wraps marked, adding the ability to see whether
  + * Class that wraps commonmark, adding the ability to see whether
  * a given message actually uses any markdown syntax or whether
  * it's plain text.
  */
  @@ -33,11 +33,7 @@ export default class Markdown {
  // running the parser on the tokens with a dummy
  // rendered and seeing if any of the renderer's
  // functions are called other than those noted below.
  - // In case you were wondering, no we can't just examine
  - // the tokens because the tokens we have are only the
  - // output of the *first* tokenizer: any line-based
  - // markdown is processed by marked within Parser by
  - // the 'inline lexer'...
  + // TODO: can't we just examine the output of the parser?
  let is_plain = true;
  function setNotPlain() {
  @@ -85,6 +81,12 @@ export default class Markdown {
  return rendered;
  }
  + /*
  + * Render the mrkdown message to plain text. That is, essentially
  + * just remove any backslashes escaping what would otherwise be
  + * markdown syntax
  + * (to fix https://github.com/vector-im/riot-web/issues/2870)
  + */
  toPlaintext() {
  const real_paragraph = this.renderer.paragraph;
  