diff --git a/academyFIVE__AddSelectBox.user.js b/academyFIVE__AddSelectBox.user.js
index 159e9cc..8901a9d 100644
--- a/academyFIVE__AddSelectBox.user.js
+++ b/academyFIVE__AddSelectBox.user.js
@@ -1,7 +1,7 @@
 // ==UserScript==
 // @name         academyFIVE::AddSelectBox
 // @namespace    dakp/academyfive
-// @version      2026.04.003
+// @version      2026.04.005
 // @description  Füge Selectbox für Kohorten/Planungsgruppen hinzu
 // @author       Dims Akpan
 // @match        https://a5.fhdw-hannover.de/*
@@ -15,25 +15,10 @@
 (function() {
     'use strict';
 
-    function getDropdownSelector() {
-        const url = window.location.href;
-        if (url.includes('/course/planning-group/list')) {
-            return 'select[name="cohort-ids[]"]';
-        }
-        if (url.includes('/course/list')) {
-            return 'select[name="planningGroupIds[]"]';
-        }
-        return null;
-    }
+    // ─── Gemeinsame Hilfsfunktionen ───────────────────────────────────────────
 
-    function tryInsertButtons() {
-        const selector = getDropdownSelector();
-        if (!selector) return false;
-
-        // Bootstrap Select wraps the <select> in .btn-group.bootstrap-select —
-        // suche die searchbox direkt über den select-Namen um sicherzustellen,
-        // dass Bootstrap Select bereits initialisiert hat
-        const select = document.querySelector(selector);
+    function insertSelectButtons(selectSelector) {
+        const select = document.querySelector(selectSelector);
         if (!select) return false;
 
         const dropdownContainer = select.closest('.btn-group.bootstrap-select');
@@ -56,29 +41,66 @@
         `;
 
         searchBox.insertAdjacentElement('afterend', actionsBox);
-        console.log('Select/Deselect Buttons erfolgreich eingefügt');
+        console.log('Select/Deselect Buttons eingefügt für:', selectSelector);
         return true;
     }
 
-    function waitForElement() {
-        if (tryInsertButtons()) return;
+    function waitAndInsert(tryFn) {
+        if (tryFn()) return;
 
-        // Bootstrap Select läuft nach DOMContentLoaded — beobachte DOM-Mutationen
         const observer = new MutationObserver(() => {
-            if (tryInsertButtons()) {
-                observer.disconnect();
-            }
+            if (tryFn()) observer.disconnect();
         });
 
         observer.observe(document.body, { childList: true, subtree: true });
 
-        // Sicherheitsnetz: nach 10 s aufgeben
-        setTimeout(() => observer.disconnect(), 10000);
+        // Polling für initialen Seitenaufruf (Bootstrap Select initialisiert sich
+        // asynchron nach DOMContentLoaded)
+        let attempts = 0;
+        const poll = setInterval(() => {
+            attempts++;
+            if (tryFn() || attempts >= 50) {
+                clearInterval(poll);
+                if (attempts >= 50) observer.disconnect();
+            }
+        }, 100);
+    }
+
+    // ─── /course/list ─────────────────────────────────────────────────────────
+
+    function courseList_tryInsert() {
+        return insertSelectButtons('select[name="planningGroupIds[]"]');
+    }
+
+    function courseList_init() {
+        waitAndInsert(courseList_tryInsert);
+    }
+
+    // ─── /course/planning-group/list ──────────────────────────────────────────
+
+    function planningGroupList_tryInsert() {
+        return insertSelectButtons('select[name="cohort-ids[]"]');
+    }
+
+    function planningGroupList_init() {
+        waitAndInsert(planningGroupList_tryInsert);
+    }
+
+    // ─── Routing ──────────────────────────────────────────────────────────────
+
+    function init() {
+        const url = window.location.href;
+
+        if (url.includes('/course/planning-group/list')) {
+            planningGroupList_init();
+        } else if (url.includes('/course/list')) {
+            courseList_init();
+        }
     }
 
     if (document.readyState === 'loading') {
-        document.addEventListener('DOMContentLoaded', waitForElement);
+        document.addEventListener('DOMContentLoaded', init);
     } else {
-        waitForElement();
+        init();
     }
-})();
\ No newline at end of file
+})();