I have this error and can not add events. It shows after 5.3.2 HotSpots update.
The error is only in backend. With Hotspots disabled it works
Fatal error: Call to undefined method CompojoomHtmlBehavior::jqueryui() in /var/www/t/u/u46862/public_html/administrator/components/com_matukio/layouts/locationfilter.php on line 13