Internal error

[ZgYEWgkvEAqD2Nnrub81GAAAAA8] /cbg/index.php?title=Special:AllMessages Error from line 54 of /var/www/html/prod/cbg/includes/specials/SpecialAllMessages.php: Call to undefined method MediaWiki\MediaWikiServices::getContentLanguage()

Backtrace:

#0 /var/www/html/prod/cbg/includes/specialpage/SpecialPage.php(565): SpecialAllMessages->execute(NULL)
#1 /var/www/html/prod/cbg/includes/specialpage/SpecialPageFactory.php(568): SpecialPage->run(NULL)
#2 /var/www/html/prod/cbg/includes/MediaWiki.php(288): SpecialPageFactory::executePath(Title, RequestContext)
#3 /var/www/html/prod/cbg/includes/MediaWiki.php(818): MediaWiki->performRequest()
#4 /var/www/html/prod/cbg/includes/MediaWiki.php(524): MediaWiki->main()
#5 /var/www/html/prod/cbg/index.php(42): MediaWiki->run()
#6 {main}