MediaWiki internal error.

Original exception: [8fdca899447897f01697c0ec] /index.php?title=Talk:Main_Page&action=edit&redlink=1 MWUnknownContentModelException: The content model 'flow-board' is not registered on this wiki.
See https://www.mediawiki.org/wiki/Content_handlers to find out which extensions handle this content model.
Backtrace:
from /home/onewqdcw/public_html/includes/content/ContentHandlerFactory.php(203)
#0 /home/onewqdcw/public_html/includes/content/ContentHandlerFactory.php(272): MediaWiki\Content\ContentHandlerFactory->validateContentHandler(string, NULL)
#1 /home/onewqdcw/public_html/includes/content/ContentHandlerFactory.php(191): MediaWiki\Content\ContentHandlerFactory->createContentHandlerFromHook(string)
#2 /home/onewqdcw/public_html/includes/content/ContentHandlerFactory.php(97): MediaWiki\Content\ContentHandlerFactory->createForModelID(string)
#3 /home/onewqdcw/public_html/includes/page/WikiPage.php(304): MediaWiki\Content\ContentHandlerFactory->getContentHandler(string)
#4 /home/onewqdcw/public_html/includes/page/WikiPage.php(290): WikiPage->getContentHandler()
#5 /home/onewqdcw/public_html/includes/page/Article.php(2012): WikiPage->getActionOverrides()
#6 /home/onewqdcw/public_html/includes/actions/ActionFactory.php(255): Article->getActionOverrides()
#7 /home/onewqdcw/public_html/includes/actions/ActionFactory.php(349): MediaWiki\Actions\ActionFactory->getAction(string, Article, RequestContext)
#8 /home/onewqdcw/public_html/includes/actions/Action.php(111): MediaWiki\Actions\ActionFactory->getActionName(RequestContext)
#9 /home/onewqdcw/public_html/includes/MediaWiki.php(176): Action::getActionName(RequestContext)
#10 /home/onewqdcw/public_html/includes/MediaWiki.php(887): MediaWiki->getAction()
#11 /home/onewqdcw/public_html/includes/MediaWiki.php(559): MediaWiki->main()
#12 /home/onewqdcw/public_html/index.php(53): MediaWiki->run()
#13 /home/onewqdcw/public_html/index.php(46): wfIndexMain()
#14 {main}

Exception caught inside exception handler: [8fdca899447897f01697c0ec] /index.php?title=Talk:Main_Page&action=edit&redlink=1 MWUnknownContentModelException: The content model 'flow-board' is not registered on this wiki.
See https://www.mediawiki.org/wiki/Content_handlers to find out which extensions handle this content model.
Backtrace:
from /home/onewqdcw/public_html/includes/content/ContentHandlerFactory.php(203)
#0 /home/onewqdcw/public_html/includes/content/ContentHandlerFactory.php(272): MediaWiki\Content\ContentHandlerFactory->validateContentHandler(string, NULL)
#1 /home/onewqdcw/public_html/includes/content/ContentHandlerFactory.php(191): MediaWiki\Content\ContentHandlerFactory->createContentHandlerFromHook(string)
#2 /home/onewqdcw/public_html/includes/content/ContentHandlerFactory.php(97): MediaWiki\Content\ContentHandlerFactory->createForModelID(string)
#3 /home/onewqdcw/public_html/includes/page/WikiPage.php(304): MediaWiki\Content\ContentHandlerFactory->getContentHandler(string)
#4 /home/onewqdcw/public_html/includes/page/WikiPage.php(290): WikiPage->getContentHandler()
#5 /home/onewqdcw/public_html/includes/page/Article.php(2012): WikiPage->getActionOverrides()
#6 /home/onewqdcw/public_html/includes/actions/ActionFactory.php(255): Article->getActionOverrides()
#7 /home/onewqdcw/public_html/includes/actions/ActionFactory.php(349): MediaWiki\Actions\ActionFactory->getAction(string, Article, SkinDgraph)
#8 /home/onewqdcw/public_html/includes/actions/Action.php(111): MediaWiki\Actions\ActionFactory->getActionName(SkinDgraph)
#9 /home/onewqdcw/public_html/includes/skins/SkinTemplate.php(94): Action::getActionName(SkinDgraph)
#10 /home/onewqdcw/public_html/includes/skins/SkinTemplate.php(67): SkinTemplate->setupTemplateContext()
#11 /home/onewqdcw/public_html/includes/skins/SkinTemplate.php(302): SkinTemplate->setupTemplateForOutput()
#12 /home/onewqdcw/public_html/includes/skins/SkinTemplate.php(127): SkinTemplate->prepareQuickTemplate()
#13 /home/onewqdcw/public_html/includes/skins/SkinTemplate.php(144): SkinTemplate->generateHTML()
#14 /home/onewqdcw/public_html/includes/OutputPage.php(2644): SkinTemplate->outputPage()
#15 /home/onewqdcw/public_html/includes/exception/MWException.php(193): OutputPage->output()
#16 /home/onewqdcw/public_html/includes/exception/MWException.php(231): MWException->reportHTML()
#17 /home/onewqdcw/public_html/includes/exception/MWExceptionHandler.php(105): MWException->report()
#18 /home/onewqdcw/public_html/includes/exception/MWExceptionHandler.php(202): MWExceptionHandler::report(MWUnknownContentModelException)
#19 /home/onewqdcw/public_html/includes/MediaWiki.php(578): MWExceptionHandler::handleException(MWUnknownContentModelException, string)
#20 /home/onewqdcw/public_html/index.php(53): MediaWiki->run()
#21 /home/onewqdcw/public_html/index.php(46): wfIndexMain()
#22 {main}