Fatal error: OOUI\Exception: OOUI\Theme::singleton was called with no singleton theme set. in /var/www/u1890974/data/www/wiki.aprelteam.su/vendor/oojs/oojs-ui/php/Theme.php:31
Stack trace:
#0 /var/www/u1890974/data/www/wiki.aprelteam.su/vendor/oojs/oojs-ui/php/Element.php(259): OOUI\Theme::singleton()
#1 /var/www/u1890974/data/www/wiki.aprelteam.su/vendor/oojs/oojs-ui/php/Tag.php(510): OOUI\Element->toString()
#2 /var/www/u1890974/data/www/wiki.aprelteam.su/extensions/VisualEditor/includes/Hooks.php(252): OOUI\Tag->__toString()
#3 /var/www/u1890974/data/www/wiki.aprelteam.su/includes/HookContainer/HookContainer.php(159): MediaWiki\Extension\VisualEditor\Hooks->onTextSlotDiffRendererTablePrefix(Object(TextSlotDiffRenderer), Object(MediaWiki\Context\RequestContext), Array)
#4 /var/www/u1890974/data/www/wiki.aprelteam.su/includes/HookContainer/HookRunner.php(1338): MediaWiki\HookContainer\HookContainer->run('TextSlotDiffRen...', Array)
#5 /var/www/u1890974/data/www/wiki.aprelteam.su/includes/diff/TextSlotDiffRenderer.php(278): MediaWiki\HookContainer\HookRunner->onTextSlotDiffRendererTablePrefix(Object(TextSlotDiffRenderer), Object(MediaWiki\Context\RequestContext), Array)
#6 /var/www/u1890974/data/www/wiki.aprelteam.su/includes/diff/DifferenceEngine.php(1048): TextSlotDiffRenderer->getTablePrefix(Object(MediaWiki\Context\RequestContext), Object(MediaWiki\Title\Title))
#7 /var/www/u1890974/data/www/wiki.aprelteam.su/includes/diff/DifferenceEngine.php(1028): DifferenceEngine->showTablePrefixes()
#8 /var/www/u1890974/data/www/wiki.aprelteam.su/includes/page/Article.php(1004): DifferenceEngine->showDiffPage(false)
#9 /var/www/u1890974/data/www/wiki.aprelteam.su/includes/page/Article.php(503): Article->showDiffPage()
#10 /var/www/u1890974/data/www/wiki.aprelteam.su/includes/actions/ViewAction.php(78): Article->view()
#11 /var/www/u1890974/data/www/wiki.aprelteam.su/includes/actions/ActionEntryPoint.php(733): ViewAction->show()
#12 /var/www/u1890974/data/www/wiki.aprelteam.su/includes/actions/ActionEntryPoint.php(510): MediaWiki\Actions\ActionEntryPoint->performAction(Object(Article), Object(MediaWiki\Title\Title))
#13 /var/www/u1890974/data/www/wiki.aprelteam.su/includes/actions/ActionEntryPoint.php(145): MediaWiki\Actions\ActionEntryPoint->performRequest()
#14 /var/www/u1890974/data/www/wiki.aprelteam.su/includes/MediaWikiEntryPoint.php(199): MediaWiki\Actions\ActionEntryPoint->execute()
#15 /var/www/u1890974/data/www/wiki.aprelteam.su/index.php(58): MediaWiki\MediaWikiEntryPoint->run()
#16 {main} in /var/www/u1890974/data/www/wiki.aprelteam.su/vendor/oojs/oojs-ui/php/Tag.php on line 512