We just upgraded from Mediawiki 1.36 to 1.38. Medik is having trouble with 1.38:
Deprecated: Use of BaseTemplate::getAfterPortlet was deprecated in MediaWiki 1.35. [Called from MedikTemplate::getPortlet in /var/www/html/w/skins/medik/includes/MedikTemplate.php at line 622] in /var/www/html/w/includes/debug/MWDebug.php on line 377