Breadcrumbs are cached
Breadcrumbs for nodes have no cache tags. The reason is that the node entity has no specific breadcrumb builder. The generic path based breadcrumb builder gets the title from the title resolver and is not aware where the title is from and what tag it should set.

You can add tags for nodes in hook_system_breadcrumb alter():

function mymodule_system_breadcrumb_alter(\Drupal\Core\Breadcrumb\Breadcrumb &amp;$breadcrumb, \Drupal\Core\Routing\RouteMatchInterface $route_match, array $context) {
  if ($route_match &amp;&amp; $node = $route_match-&gt;getParameter('node')) {
    $breadcrumb-&gt;addCacheableDependency($node);
  }
}


To test this you need to have extended the breadcrumb behavior to display the title. In my test site this was the Bootstrap theme. Another option would be the module Current Page Crumb.