message: Fix `useful-not-found-page` again
  Kinda fixes
  Tested on
diff: @@ -78,7 +78,7 @@ async function addDefaultBranchLink(bar) {
  function init() {
  const parts = parseCurrentURL();
  - if (parts.length <= 1) {
  + if (parts.length <= 1 || !select.exists('[alt*="This is not the web page you are looking for"]')) {
  return false;
  }
  @@ -99,7 +99,7 @@ function init() {
  }
  }
  - select('#js-pjax-container > :first-child').after(bar);
  + select('main > :first-child').after(bar);
  // Check parts from right to left; skip the last part
  for (let i = bar.children.length - 2; i >= 0; i--) {
  