message: Use underscore for <em> when doing html > md
  to be consistent with the format bar, which also uses underscores for italics
diff: @@ -90,7 +90,7 @@ function parseElement(n, partCreator, state) {
  case "BR":
  return partCreator.newline();
  case "EM":
  - return partCreator.plain(`*${n.textContent}*`);
  + return partCreator.plain(`_${n.textContent}_`);
  case "STRONG":
  return partCreator.plain(`**${n.textContent}**`);
  case "PRE":
  