fix: [main] Prevent setting listeners if dependencies are not loaded

webroot/js/main.js

@@ -279,10 +279,12 @@ $(document).ready(() => {
     overloadBSDropdown();
     addSupportOfNestedDropdown();
 
+    if (window.debounce) {
         const debouncedGlobalSearch = debounce(performGlobalSearch, 400)
         $('#globalSearch')
             .keydown(debouncedGlobalSearch)
             .keydown(focusSearchResults);
+    }
 
     $('.lock-sidebar a.btn-lock-sidebar').click(() => {
         const $sidebar = $('.sidebar')