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.

return parseJS(state, style, type, content, stream);
    },
    indent: function(state, textAfter) {
      if (state.tokenize == jsTokenComment) return CodeMirror.Pass;
      if (state.tokenize != jsTokenBase) return 0;
      var firstChar = textAfter && textAfter.charAt(0), lexical = state.lexical;
      if (lexical.type == "stat" && firstChar == "}") lexical = lexical.prev;
      var type = lexical.type, closing = firstChar == type;
      if (type == "vardef") return lexical.indented + (state.lastType == "operator" || state.lastType == "," ? 4 : 0);
      else if (type == "form" && firstChar == "{") return lexical.indented;
      else if (type == "form") return lexical.indented + indentUnit;
      else if (type == "stat")
        return lexical.indented + (state.lastType == "operator" || state.lastType == "," ? indentUnit : 0);
      else if (lexical.info == "switch" && !closing)
        return lexical.indented + (/^(?:case|default)\b/.test(textAfter) ? indentUnit : 2 * indentUnit);
      else if (lexical.align) return lexical.column + (closing ? 0 : 1);
      else return lexical.indented + (closing ? 0 : indentUnit);
    },
    electricChars: ":{}",
    jsonMode: jsonMode
  };
});
CodeMirror.defineMIME("text/javascript", "javascript");
CodeMirror.defineMIME("text/ecmascript", "javascript");
CodeMirror.defineMIME("application/javascript", "javascript");
CodeMirror.defineMIME("application/ecmascript", "javascript");
CodeMirror.defineMIME("application/json", {name: "javascript", json: true});
CodeMirror.defineMIME("text/typescript", { name: "javascript", typescript: true });
CodeMirror.defineMIME("application/typescript", { name: "javascript", typescript: true });