message: Don't do anything when not logged into GitHub
diff: @@ -436,6 +436,11 @@ function sortMilestonesByClosestDueDate() {
  }
  function init() {
  + const username = getUsername();
  + if (!username) {
  + return;
  + }
  +
  if (select.exists('html.refined-github')) {
  console.count('Refined GitHub was loaded multiple times: https://github.com/sindresorhus/refined-github/issues/479');
  return;
  @@ -495,7 +500,9 @@ async function onDomReady() {
  markUnread.setup();
  + if (!pageDetect.isGist()) {
  moveMarketplaceLinkToProfileDropdown();
  + }
  if (pageDetect.isGist()) {
  addGistCopyButton();
  