Merge branch '5.4'

diff --cc wcfsetup/install/files/options.inc.php
index 87e1f5ea2f032e1abf3d6faddb958e0fcdc9f02a,edfa6df09147c6721ba2d6b44f098c9fad4c5724..1110de5f7bc7b402ff84d9da2ac0316f83d706e1
--- 1/wcfsetup/install/files/options.inc.php
--- 2/wcfsetup/install/files/options.inc.php
+++ b/wcfsetup/install/files/options.inc.php
@@@ -22,10 -22,14 +22,10 @@@ if (\file_exists(WCF_DIR . 'cookiePrefi
  \define('COOKIE_PATH', '');
  \define('COOKIE_DOMAIN', '');
  
- \define('HTTP_SEND_X_FRAME_OPTIONS', 0);
+ \define('HTTP_SEND_X_FRAME_OPTIONS', 1);
  
 -\define('BLACKLIST_IP_ADDRESSES', '');
 -\define('BLACKLIST_USER_AGENTS', '');
 -
  \define('CACHE_SOURCE_TYPE', 'disk');
  \define('IMAGE_ADAPTER_TYPE', 'gd');
 -\define('MODULE_MASTER_PASSWORD', 0);
  \define('TIMEZONE', 'Europe/Berlin');
  
  \define('ENABLE_DEBUG_MODE', 1);