diff --git a/lib/private/server.php b/lib/private/server.php
index 43a41cbc01c98..9a254b55f33ca 100644
--- a/lib/private/server.php
+++ b/lib/private/server.php
@@ -567,7 +567,13 @@ public function __construct($webRoot, \OC\Config $config) {
 			return $factory->getManager();
 		});
 		$this->registerService('ThemingDefaults', function(Server $c) {
-			if(class_exists('OCA\Theming\Template', false) && $this->getConfig()->getSystemValue('installed', false) && $this->getAppManager()->isInstalled('theming')) {
+			try {
+				$classExists = class_exists('OCA\Theming\Template');
+			} catch (\OCP\AutoloadNotAllowedException $e) {
+				// App disabled or in maintenance mode
+				$classExists = false;
+			}
+			if ($classExists && $this->getConfig()->getSystemValue('installed', false) && $this->getAppManager()->isInstalled('theming')) {
 				return new Template(
 					$this->getConfig(),
 					$this->getL10N('theming'),
diff --git a/lib/private/urlgenerator.php b/lib/private/urlgenerator.php
index ee4ce349ea23a..62649781c353e 100644
--- a/lib/private/urlgenerator.php
+++ b/lib/private/urlgenerator.php
@@ -29,7 +29,8 @@
  */
 
 namespace OC;
-use OC_Defaults;
+
+
 use OCP\ICacheFactory;
 use OCP\IConfig;
 use OCP\IURLGenerator;