Universal export: Error

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#0 /opt/mediawiki/w/extensions/BlueSpiceUniversalExport/includes/specials/SpecialUniversalExport.class.php(117): SpecialUniversalExport->processParameter('GTK_demo_launch...')
#1 /opt/mediawiki/w/includes/specialpage/SpecialPage.php(565): SpecialUniversalExport->execute('GTK_demo_launch...')
#2 /opt/mediawiki/w/includes/specialpage/SpecialPageFactory.php(568): SpecialPage->run('GTK_demo_launch...')
#3 /opt/mediawiki/w/includes/MediaWiki.php(288): SpecialPageFactory::executePath(Object(Title), Object(RequestContext))
#4 /opt/mediawiki/w/includes/MediaWiki.php(818): MediaWiki->performRequest()
#5 /opt/mediawiki/w/includes/MediaWiki.php(524): MediaWiki->main()
#6 /opt/mediawiki/w/index.php(42): MediaWiki->run()
#7 {main}