Steps to reproduce:
Found it in logstash: https://logstash.wikimedia.org/app/kibana#/doc/logstash-*/logstash-2017.07.28/mediawiki?id=AV2Ju-H5CtkHCY6a4ZIr&_g=()
PHP Error: Argument 1 passed to MediaWiki\Linker\LinkRenderer::makeLink() must implement interface MediaWiki\Linker\LinkTarget, null given t exception.trace #0 /srv/mediawiki/php-1.30.0-wmf.11/includes/linker/LinkRenderer.php(154): MWExceptionHandler::handleError(integer, string, string, integer, array, array) #1 /srv/mediawiki/php-1.30.0-wmf.11/includes/actions/InfoAction.php(239): MediaWiki\Linker\LinkRenderer->makeLink(NULL) #2 /srv/mediawiki/php-1.30.0-wmf.11/includes/actions/InfoAction.php(120): InfoAction->pageInfo() #3 /srv/mediawiki/php-1.30.0-wmf.11/includes/actions/FormlessAction.php(43): InfoAction->onView() #4 /srv/mediawiki/php-1.30.0-wmf.11/includes/MediaWiki.php(499): FormlessAction->show() #5 /srv/mediawiki/php-1.30.0-wmf.11/includes/MediaWiki.php(293): MediaWiki->performAction(Article, Title) #6 /srv/mediawiki/php-1.30.0-wmf.11/includes/MediaWiki.php(868): MediaWiki->performRequest() #7 /srv/mediawiki/php-1.30.0-wmf.11/includes/MediaWiki.php(523): MediaWiki->main() #8 /srv/mediawiki/php-1.30.0-wmf.11/index.php(43): MediaWiki->run() #9 /srv/mediawiki/w/index.php(3): include(string) #10 {main}
The page is not a redirect but ActionInfo thinks so