diff --git a/course/classes/category.php b/course/classes/category.php
index cb482053ca3..0a8af94f8d7 100644
--- a/course/classes/category.php
+++ b/course/classes/category.php
@@ -900,7 +900,7 @@ class core_course_category implements renderable, cacheable_object, IteratorAggr
         // Trigger a purge for all caches listening for changes to category enrolment.
         cache_helper::purge_by_event('changesincategoryenrolment');
 
-        if (!$CFG->coursecontact || !in_array($roleid, explode(',', $CFG->coursecontact))) {
+        if (empty($CFG->coursecontact) || !in_array($roleid, explode(',', $CFG->coursecontact))) {
             // The role is not one of course contact roles.
             return;
         }