diff --git a/apps/theming/lib/Service/BackgroundService.php b/apps/theming/lib/Service/BackgroundService.php
index bf6508744487c..d403e77635c11 100644
--- a/apps/theming/lib/Service/BackgroundService.php
+++ b/apps/theming/lib/Service/BackgroundService.php
@@ -18,6 +18,7 @@
 use OCP\Files\NotPermittedException;
 use OCP\Files\SimpleFS\ISimpleFile;
 use OCP\Files\SimpleFS\ISimpleFolder;
+use OCP\IAppConfig;
 use OCP\IConfig;
 use OCP\Lock\LockedException;
 use OCP\PreConditionNotMetException;
@@ -200,6 +201,7 @@ class BackgroundService {
 	public function __construct(
 		private IRootFolder $rootFolder,
 		private IAppData $appData,
+		private IAppConfig $appConfig,
 		private IConfig $config,
 		private ?string $userId,
 	) {
@@ -328,7 +330,7 @@ public function setGlobalBackground($path): ?string {
 		if ($handle && $image->loadFromFileHandle($handle) !== false) {
 			$meanColor = $this->calculateMeanColor($image);
 			if ($meanColor !== false) {
-				$this->config->setAppValue(Application::APP_ID, 'background_color', $meanColor);
+				$this->appConfig->setValueString(Application::APP_ID, 'background_color', $meanColor);
 				return $meanColor;
 			}
 		}
diff --git a/lib/private/Server.php b/lib/private/Server.php
index 19c3b72c11c4a..2faae765960ef 100644
--- a/lib/private/Server.php
+++ b/lib/private/Server.php
@@ -1041,6 +1041,7 @@ public function __construct($webRoot, \OC\Config $config) {
 				$backgroundService = new BackgroundService(
 					$c->get(IRootFolder::class),
 					$c->getAppDataDir('theming'),
+					$c->get(IAppConfig::class),
 					$c->get(\OCP\IConfig::class),
 					$c->get(ISession::class)->get('user_id'),
 				);