diff --git a/partials/landingpage/accountsetup/system.php b/partials/landingpage/accountsetup/system.php
index 4fe5b74..9b5b033 100644
--- a/partials/landingpage/accountsetup/system.php
+++ b/partials/landingpage/accountsetup/system.php
@@ -50,4 +50,5 @@ require dirname(__DIR__) . '/../structure/layout_start.php';
       </div>
     </form>
   </dialog>
+<?php tpl_add_script(app_asset_url('/assets/js/account.js'), 'footer', false, false, '', null, true); ?>
 <?php require dirname(__DIR__) . '/../structure/layout_end.php'; ?>
diff --git a/partials/structure/header.php b/partials/structure/header.php
index c523024..7e9c3b7 100644
--- a/partials/structure/header.php
+++ b/partials/structure/header.php
@@ -4,6 +4,7 @@ $appBaseUrl = $layoutContext['app_base_url'] ?? '';
 
 $navLinks = $navLinks ?? [
     ['id' => 'dashboard', 'label' => 'Dashboard',      'href' => $appBaseUrl . '/admin/dashboard.php'],
+    ['id' => 'system',    'label' => 'Systemeinstellungen', 'href' => $appBaseUrl . '/admin/system.php'],
     ['id' => 'settings',  'label' => 'API & Tabellen', 'href' => $appBaseUrl . '/admin/settings.php'],
     ['id' => 'users',     'label' => 'Userverwaltung', 'href' => $appBaseUrl . '/admin/users.php'],
     ['id' => 'profile',   'label' => 'Mein Konto',     'href' => $appBaseUrl . '/admin/profile.php'],
@@ -48,6 +49,7 @@ $showNavLinks = !$hasHeaderTabs && !empty($navLinks);
                 <div id="userMenuPanel" class="user-menu hidden" role="menu">
                     <a href="<?= htmlspecialchars($appBaseUrl . '/admin/profile.php') ?>" class="user-menu-item" data-menu="profile">Profil</a>
                     <a href="<?= htmlspecialchars($appBaseUrl . '/admin/dashboard.php') ?>" class="user-menu-item" data-role="admin">Dashboard</a>
+                    <a href="<?= htmlspecialchars($appBaseUrl . '/admin/system.php') ?>" class="user-menu-item" data-role="admin">Systemverwaltung</a>
                     <a href="<?= htmlspecialchars($appBaseUrl . '/admin/settings.php') ?>" class="user-menu-item" data-role="admin">API & Tabellen</a>
                     <a href="<?= htmlspecialchars($appBaseUrl . '/admin/users.php') ?>" class="user-menu-item" data-role="owner">Userverwaltung</a>
                     <button id="btn-logout" type="button" class="user-menu-item text-red-600">Logout</button>
diff --git a/src/ApiKernel.php b/src/ApiKernel.php
index f754d4b..fd2aeb0 100644
--- a/src/ApiKernel.php
+++ b/src/ApiKernel.php
@@ -1094,9 +1094,23 @@ class ApiKernel
         $auth = $this->requireAuth();
         $customerId = (int)($auth['customer_id'] ?? 0);
         $defaults = $this->resolveLegacySectionDefaults($kind);
-        $section = $defaults['is_template']
-            ? $this->ensureEmailtemplateSection($customerId)
-            : $this->ensureContentSection($customerId, $defaults['name'], $defaults['slug'], false);
+        if ($defaults['is_template']) {
+            $section = $this->ensureEmailtemplateSection($customerId);
+        } else {
+            $section = $this->fetchContentSectionBySlug($customerId, $defaults['slug']);
+        }
+        if (!$section) {
+            $this->respond([
+                'ok' => true,
+                'kind' => 'content',
+                'items' => [],
+                'data' => [],
+                'count' => 0,
+                'offset' => 0,
+                'limit' => 0,
+            ]);
+            return;
+        }
         $this->handleContentList($section);
     }
 
@@ -1105,9 +1119,12 @@ class ApiKernel
         $auth = $this->requireAuth();
         $customerId = (int)($auth['customer_id'] ?? 0);
         $defaults = $this->resolveLegacySectionDefaults($kind);
-        $section = $defaults['is_template']
-            ? $this->ensureEmailtemplateSection($customerId)
-            : $this->ensureContentSection($customerId, $defaults['name'], $defaults['slug'], false);
+        if ($defaults['is_template']) {
+            $section = $this->ensureEmailtemplateSection($customerId);
+        } else {
+            $section = $this->fetchContentSectionBySlug($customerId, $defaults['slug']);
+        }
+        if (!$section) $this->fail('section not configured', ['kind' => $kind], 404);
         $this->handleContentGet($section);
     }
 
@@ -1116,9 +1133,12 @@ class ApiKernel
         $auth = $this->requireAuth();
         $customerId = (int)($auth['customer_id'] ?? 0);
         $defaults = $this->resolveLegacySectionDefaults($kind);
-        $section = $defaults['is_template']
-            ? $this->ensureEmailtemplateSection($customerId)
-            : $this->ensureContentSection($customerId, $defaults['name'], $defaults['slug'], false);
+        if ($defaults['is_template']) {
+            $section = $this->ensureEmailtemplateSection($customerId);
+        } else {
+            $section = $this->fetchContentSectionBySlug($customerId, $defaults['slug']);
+        }
+        if (!$section) $this->fail('section not configured', ['kind' => $kind], 404);
         $this->handleContentCreate($section);
     }
 
@@ -1127,9 +1147,12 @@ class ApiKernel
         $auth = $this->requireAuth();
         $customerId = (int)($auth['customer_id'] ?? 0);
         $defaults = $this->resolveLegacySectionDefaults($kind);
-        $section = $defaults['is_template']
-            ? $this->ensureEmailtemplateSection($customerId)
-            : $this->ensureContentSection($customerId, $defaults['name'], $defaults['slug'], false);
+        if ($defaults['is_template']) {
+            $section = $this->ensureEmailtemplateSection($customerId);
+        } else {
+            $section = $this->fetchContentSectionBySlug($customerId, $defaults['slug']);
+        }
+        if (!$section) $this->fail('section not configured', ['kind' => $kind], 404);
         $this->handleContentUpdate($section);
     }
 
@@ -1138,9 +1161,12 @@ class ApiKernel
         $auth = $this->requireAuth();
         $customerId = (int)($auth['customer_id'] ?? 0);
         $defaults = $this->resolveLegacySectionDefaults($kind);
-        $section = $defaults['is_template']
-            ? $this->ensureEmailtemplateSection($customerId)
-            : $this->ensureContentSection($customerId, $defaults['name'], $defaults['slug'], false);
+        if ($defaults['is_template']) {
+            $section = $this->ensureEmailtemplateSection($customerId);
+        } else {
+            $section = $this->fetchContentSectionBySlug($customerId, $defaults['slug']);
+        }
+        if (!$section) $this->fail('section not configured', ['kind' => $kind], 404);
         $this->handleContentDelete($section);
     }