diff --git a/mod_form.php b/mod_form.php
index a15524d..de5cf8a 100644
--- a/mod_form.php
+++ b/mod_form.php
@@ -62,8 +62,6 @@ public function definition() {
         $mform->setExpanded('section-refcourse');
         $mform->addHelpButton('section-refcourse', 'refcourse', 'subcourse');
 
-        $mycourses = subcourse_available_courses();
-
         $currentrefcourseid = isset($this->current->refcourse) ? $this->current->refcourse : null;
         $currentrefcoursename = null;
         $currentrefcourseavailable = false;
@@ -86,11 +84,8 @@ public function definition() {
 
             } else {
                 // Check if the currently set value is still available.
-                foreach ($mycourses as $mycourse) {
-                    if ($mycourse->id == $currentrefcourseid) {
-                        $currentrefcourseavailable = true;
-                        break;
-                    }
+                if (has_capability('moodle/grade:viewall', context_course::instance($currentrefcourseid))) {
+                    $currentrefcourseavailable = true;
                 }
             }
         }
@@ -105,37 +100,10 @@ public function definition() {
             $includekeepref = true;
         }
 
-        $options = [get_string('none')];
-
-        if (empty($mycourses)) {
-            if (empty($includekeepref)) {
-                $options = [0 => get_string('nocoursesavailable', 'subcourse')];
-                $mform->addElement('select', 'refcourse', get_string('refcourselabel', 'subcourse'), $options);
-            } else {
-                $mform->addElement('hidden', 'refcourse', 0);
-                $mform->setType('refcourse', PARAM_INT);
-            }
-
-        } else {
-            $catlist = core_course_category::make_categories_list('', 0, ' / ');
-
-            foreach ($mycourses as $mycourse) {
-                $courselabel = $catlist[$mycourse->category] . ' / ' . $mycourse->fullname.' ('.$mycourse->shortname.')';
-                if (empty($mycourse->visible)) {
-                    if ($config->displayhiddencourses || $mycourse->id == $currentrefcourseid) {
-                        $hiddenlabel = ' '.get_string('hiddencourse', 'subcourse');
-                        $options[$mycourse->id] = $courselabel.$hiddenlabel;
-                    }
-                } else {
-                    $options[$mycourse->id] = $courselabel;
-                }
-            }
+        $mform->addElement('course', 'refcourse', get_string('refcourselabel', 'subcourse'), ['limittoenrolled' => 1]);
 
-            $mform->addElement('autocomplete', 'refcourse', get_string('refcourselabel', 'subcourse'), $options);
-
-            if (!empty($includekeepref)) {
-                $mform->disabledIf('refcourse', 'refcoursecurrent', 'checked');
-            }
+        if (!empty($includekeepref)) {
+            $mform->disabledIf('refcourse', 'refcoursecurrent', 'checked');
         }
 
         $mform->addElement('header', 'section-gradesfetching', get_string('gradesfetching', 'subcourse'));