diff --git a/core/lib/Drupal/Core/Routing/Enhancer/RouteEnhancerInterface.php b/core/lib/Drupal/Core/Routing/Enhancer/RouteEnhancerInterface.php
index 369aba9c9d..85f9e7a3a5 100644
--- a/core/lib/Drupal/Core/Routing/Enhancer/RouteEnhancerInterface.php
+++ b/core/lib/Drupal/Core/Routing/Enhancer/RouteEnhancerInterface.php
@@ -13,6 +13,8 @@
  * @deprecated in Drupal 8.4.0 and will be removed before Drupal 9.0.0. Instead,
  * you should use Symfony\Cmf\Component\Routing\Enhancer\RouteEnhancerInterface.
  * See https://www.drupal.org/node/2894934
+ * Part of the deprecation means that applies() is now called on runtime instead
+ * of compile time.
  */
 interface RouteEnhancerInterface extends BaseRouteEnhancerInterface {
 
diff --git a/core/lib/Drupal/Core/Routing/Router.php b/core/lib/Drupal/Core/Routing/Router.php
index 595630c35d..13c7a8196b 100644
--- a/core/lib/Drupal/Core/Routing/Router.php
+++ b/core/lib/Drupal/Core/Routing/Router.php
@@ -282,7 +282,7 @@ protected function applyRouteFilters(RouteCollection $collection, Request $reque
     // Route filters are expected to throw an exception themselves if they
     // end up filtering the list down to 0.
     foreach ($this->filters as $filter) {
-      // @todo should we respect ::applies()? The problem is that we can't, because no route has been matched yet. So we should probably remove \Drupal\Core\Routing\RouteFilterInterface?
+      // @todo should we respect ::applies()? The problem is that we can't,because no route has been matched yet. So we should probably remove \Drupal\Core\Routing\RouteFilterInterface?
       $collection = $filter->filter($collection, $request);
     }