diff --git a/core/lib/Drupal/Core/RouteProcessor/RouteProcessorCurrent.php b/core/lib/Drupal/Core/RouteProcessor/RouteProcessorCurrent.php
index efafdcc..4d57843 100644
--- a/core/lib/Drupal/Core/RouteProcessor/RouteProcessorCurrent.php
+++ b/core/lib/Drupal/Core/RouteProcessor/RouteProcessorCurrent.php
@@ -40,6 +40,8 @@ public function processOutbound($route_name, Route $route, array &$parameters, C
     if ($route_name === '<current>') {
       if ($current_route = $this->routeMatch->getRouteObject()) {
         $requirements = $current_route->getRequirements();
+        // Setting _method and _schema is deprecated since 2.7. Using
+        // setMethods() and setSchemes() are now the recommended ways.
         unset($requirements['_method']);
         unset($requirements['_schema']);
         $route->setRequirements($requirements);