diff --git a/app/controllers/application_controller.rb b/app/controllers/application_controller.rb
index bf37421771fa24df238182838d2d5e3ffeb4618b..81c0fa26d18e9ad767a7a65b27fcb1101ecffdd5 100644
--- a/app/controllers/application_controller.rb
+++ b/app/controllers/application_controller.rb
@@ -115,10 +115,10 @@ class ApplicationController < ActionController::Base
 
   def render_404
     respond_to do |format|
-      format.json { head :not_found }
-      format.any do
+      format.html do
         render file: Rails.root.join("public", "404"), layout: false, status: "404"
       end
+      format.any { head :not_found }
     end
   end
 
diff --git a/spec/support/test_env.rb b/spec/support/test_env.rb
index d56274d0979b64cd02a84ae120a099534d73c37f..243d671c5217f8d0d688aae97c3e93bff73f73c1 100644
--- a/spec/support/test_env.rb
+++ b/spec/support/test_env.rb
@@ -26,10 +26,10 @@ module TestEnv
     'expand-collapse-lines'              => '238e82d',
     'video'                              => '8879059',
     'crlf-diff'                          => '5938907',
-    'conflict-start'                     => '75284c7',
+    'conflict-start'                     => '824be60',
     'conflict-resolvable'                => '1450cd6',
     'conflict-binary-file'               => '259a6fb',
-    'conflict-contains-conflict-markers' => '5e0964c',
+    'conflict-contains-conflict-markers' => '78a3086',
     'conflict-missing-side'              => 'eb227b3',
     'conflict-non-utf8'                  => 'd0a293c',
     'conflict-too-large'                 => '39fa04f',