Right now we use codemirror's JavaScript mode on the website but there's a JSX mode now so we should start using that instead.

}
        }
      } else if (nextIntact && nextIntact.from <= lineN && nextIntact.to > lineN) {
        
        
        while (cur.lineObj != line) cur = rm(cur);
        if (lineNumbers && updateNumbersFrom <= lineN && cur.lineNumber)
          setTextContent(cur.lineNumber, lineNumberFor(cm.options, lineN));
        cur = cur.nextSibling;
      } else {
        
        
        
        if (line.widgets) for (var j = 0, search = cur, reuse; search && j < 20; ++j, search = search.nextSibling)
          if (search.lineObj == line && /div/i.test(search.nodeName)) { reuse = search; break; }
        
        var lineNode = buildLineElement(cm, line, lineN, dims, reuse);
        if (lineNode != reuse) {
          container.insertBefore(lineNode, cur);
        } else {
          while (cur != reuse) cur = rm(cur);
          cur = cur.nextSibling;
        }
        lineNode.lineObj = line;
      }
      ++lineN;
    });
    while (cur) cur = rm(cur);
  }
  function buildLineElement(cm, line, lineNo, dims, reuse) {