message: Persist code block language when editing
diff: @@ -58,7 +58,16 @@ function parseLink(a, partCreator) {
  function parseCodeBlock(n, partCreator) {
  const parts = [];
  - const preLines = ("```\n" + n.textContent + "```").split("\n");
  + let language = "";
  + if (n.firstChild && n.firstChild.nodeName === "CODE") {
  + for (const className of n.firstChild.classList) {
  + if (className.startsWith("language-")) {
  + language = className.substr("language-".length);
  + break;
  + }
  + }
  + }
  + const preLines = ("```" + language + "\n" + n.textContent + "```").split("\n");
  preLines.forEach((l, i) => {
  parts.push(partCreator.plain(l));
  if (i < preLines.length - 1) {
  