Issue #2392433 by Berdir: Stream wrappers are registered before page cache

core/lib/Drupal/Core/DrupalKernel.php

@@ -406,7 +406,6 @@ public function boot() {
     $seed = unpack("L", Crypt::randomBytes(4));
     mt_srand($seed[1]);
 
-    $this->container->get('stream_wrapper_manager')->register();
     $this->booted = TRUE;
 
     return $this;
@@ -440,6 +439,9 @@ public function preHandle(Request $request) {
     // Load all enabled modules.
     $this->container->get('module_handler')->loadAll();
 
+    // Register stream wrappers.
+    $this->container->get('stream_wrapper_manager')->register();
+
     // Initialize legacy request globals.
     $this->initializeRequestGlobals($request);