diff --git a/lib/private/AppFramework/Bootstrap/RegistrationContext.php b/lib/private/AppFramework/Bootstrap/RegistrationContext.php
index 988313f20e82f..72834ebbf38af 100644
--- a/lib/private/AppFramework/Bootstrap/RegistrationContext.php
+++ b/lib/private/AppFramework/Bootstrap/RegistrationContext.php
@@ -302,12 +302,20 @@ public function registerTemplateProvider(string $appId, string $class): void {
 	 */
 	public function delegateCapabilityRegistrations(array $apps): void {
 		while (($registration = array_shift($this->capabilities)) !== null) {
+			$appId = $registration['appId'];
+			if (!isset($apps[$appId])) {
+				// If we land here something really isn't right. But at least we caught the
+				// notice that is otherwise emitted for the undefined index
+				$this->logger->error("App $appId not loaded for the capability registration");
+
+				continue;
+			}
+
 			try {
-				$apps[$registration['appId']]
+				$apps[$appId]
 					->getContainer()
 					->registerCapability($registration['capability']);
 			} catch (Throwable $e) {
-				$appId = $registration['appId'];
 				$this->logger->logException($e, [
 					'message' => "Error during capability registration of $appId: " . $e->getMessage(),
 					'level' => ILogger::ERROR,
@@ -380,11 +388,20 @@ public function delegateEventListenerRegistrations(IEventDispatcher $eventDispat
 	 */
 	public function delegateContainerRegistrations(array $apps): void {
 		while (($registration = array_shift($this->services)) !== null) {
+			$appId = $registration['appId'];
+			if (!isset($apps[$appId])) {
+				// If we land here something really isn't right. But at least we caught the
+				// notice that is otherwise emitted for the undefined index
+				$this->logger->error("App $appId not loaded for the container service registration");
+
+				continue;
+			}
+
 			try {
 				/**
 				 * Register the service and convert the callable into a \Closure if necessary
 				 */
-				$apps[$registration['appId']]
+				$apps[$appId]
 					->getContainer()
 					->registerService(
 						$registration['name'],
@@ -392,7 +409,6 @@ public function delegateContainerRegistrations(array $apps): void {
 						$registration['shared'] ?? true
 					);
 			} catch (Throwable $e) {
-				$appId = $registration['appId'];
 				$this->logger->logException($e, [
 					'message' => "Error during service registration of $appId: " . $e->getMessage(),
 					'level' => ILogger::ERROR,
@@ -401,15 +417,23 @@ public function delegateContainerRegistrations(array $apps): void {
 		}
 
 		while (($registration = array_shift($this->aliases)) !== null) {
+			$appId = $registration['appId'];
+			if (!isset($apps[$appId])) {
+				// If we land here something really isn't right. But at least we caught the
+				// notice that is otherwise emitted for the undefined index
+				$this->logger->error("App $appId not loaded for the container alias registration");
+
+				continue;
+			}
+
 			try {
-				$apps[$registration['appId']]
+				$apps[$appId]
 					->getContainer()
 					->registerAlias(
 						$registration['alias'],
 						$registration['target']
 					);
 			} catch (Throwable $e) {
-				$appId = $registration['appId'];
 				$this->logger->logException($e, [
 					'message' => "Error during service alias registration of $appId: " . $e->getMessage(),
 					'level' => ILogger::ERROR,
@@ -418,17 +442,25 @@ public function delegateContainerRegistrations(array $apps): void {
 		}
 
 		while (($registration = array_shift($this->parameters)) !== null) {
+			$appId = $registration['appId'];
+			if (!isset($apps[$appId])) {
+				// If we land here something really isn't right. But at least we caught the
+				// notice that is otherwise emitted for the undefined index
+				$this->logger->error("App $appId not loaded for the container parameter registration");
+
+				continue;
+			}
+
 			try {
-				$apps[$registration['appId']]
+				$apps[$appId]
 					->getContainer()
 					->registerParameter(
 						$registration['name'],
 						$registration['value']
 					);
 			} catch (Throwable $e) {
-				$appId = $registration['appId'];
 				$this->logger->logException($e, [
-					'message' => "Error during service alias registration of $appId: " . $e->getMessage(),
+					'message' => "Error during service parameter registration of $appId: " . $e->getMessage(),
 					'level' => ILogger::ERROR,
 				]);
 			}
@@ -440,12 +472,20 @@ public function delegateContainerRegistrations(array $apps): void {
 	 */
 	public function delegateMiddlewareRegistrations(array $apps): void {
 		while (($middleware = array_shift($this->middlewares)) !== null) {
+			$appId = $middleware['appId'];
+			if (!isset($apps[$appId])) {
+				// If we land here something really isn't right. But at least we caught the
+				// notice that is otherwise emitted for the undefined index
+				$this->logger->error("App $appId not loaded for the container middleware registration");
+
+				continue;
+			}
+
 			try {
-				$apps[$middleware['appId']]
+				$apps[$appId]
 					->getContainer()
 					->registerMiddleWare($middleware['class']);
 			} catch (Throwable $e) {
-				$appId = $middleware['appId'];
 				$this->logger->logException($e, [
 					'message' => "Error during capability registration of $appId: " . $e->getMessage(),
 					'level' => ILogger::ERROR,