Merge branch '5.4'

diff --cc wcfsetup/install/files/lib/system/WCFSetup.class.php
index e058a09e0b399882e575de27bafff7fea797bdf1,510d3a498d7841c5f703c260d5b5725c31f752a7..594d51233217a9ab71f3c5c2b6453b8e74e49c35
--- 1/wcfsetup/install/files/lib/system/WCFSetup.class.php
--- 2/wcfsetup/install/files/lib/system/WCFSetup.class.php
+++ b/wcfsetup/install/files/lib/system/WCFSetup.class.php
@@@ -1351,10 -1338,15 +1352,14 @@@ class WCFSetup extends WC
          $factory = new ACPSessionFactory();
          $factory->load();
  
+         $useImagick = ImagickImageAdapter::isSupported()
+             && ImagickImageAdapter::supportsAnimatedGIFs(ImagickImageAdapter::getVersion())
+             && ImagickImageAdapter::supportsWebp();
+ 
          SessionHandler::getInstance()->changeUser($admin);
 -        SessionHandler::getInstance()->register('masterPassword', 1);
          SessionHandler::getInstance()->register('__wcfSetup_developerMode', self::$developerMode);
          SessionHandler::getInstance()->register('__wcfSetup_directories', self::$directories);
-         SessionHandler::getInstance()->register('__wcfSetup_imagick', ImagickImageAdapter::isSupported());
+         SessionHandler::getInstance()->register('__wcfSetup_imagick', $useImagick);
          SessioNHandler::getInstance()->registerReauthentication();
          SessionHandler::getInstance()->update();
  

diff --cc wcfsetup/install/lang/de.xml
Simple merge