seen in production:
Catchable fatal error: Argument 1 passed to Wikibase\Rdf\RdfBuilder::addEntityRedirect() must be an instance of Wikibase\DataModel\Entity\EntityId, null given in /srv/mediawiki/php-1.26wmf19/extensions/Wikidata/extensions/Wikibase/repo/includes/rdf/RdfBuilder.php on line 479
/wiki/Special:EntityData/Q4115189.nt ErrorException from line 479 of /srv/mediawiki/php-1.26wmf19/extensions/Wikidata/extensions/Wikibase/repo/includes/rdf/RdfBuilder.php: PHP Error: Argument 1 passed to Wikibase\Rdf\RdfBuilder::addEntityRedirect() must be an instance of Wikibase\DataModel\Entity\EntityId, null given {"exception":"[Exception ErrorException] (/srv/mediawiki/php-1.26wmf19/extensions/Wikidata/extensions/Wikibase/repo/includes/rdf/RdfBuilder.php:479) PHP Error: Argument 1 passed to Wikibase\\Rdf\\RdfBuilder::addEntityRedirect() must be an instance of Wikibase\\DataModel\\Entity\\EntityId, null given\n[stacktrace]\n#0 /srv/mediawiki/php-1.26wmf19/extensions/Wikidata/extensions/Wikibase/repo/includes/rdf/RdfBuilder.php(479): MWExceptionHandler::handleError(integer, string, string, integer)\n#1 /srv/mediawiki/php-1.26wmf19/extensions/Wikidata/extensions/Wikibase/repo/includes/LinkedData/EntityDataSerializationService.php(314): Wikibase\\Rdf\\RdfBuilder->addEntityRedirect(NULL, Wikibase\\DataModel\\Entity\\ItemId)\n#2 /srv/mediawiki/php-1.26wmf19/extensions/Wikidata/extensions/Wikibase/repo/includes/LinkedData/EntityDataSerializationService.php(290): Wikibase\\Repo\\LinkedData\\EntityDataSerializationService->addIncomingRedirects(Wikibase\\DataModel\\Entity\\ItemId, NULL, array, Wikibase\\Rdf\\RdfBuilder)\n#3 /srv/mediawiki/php-1.26wmf19/extensions/Wikidata/extensions/Wikibase/repo/includes/LinkedData/EntityDataSerializationService.php(229): Wikibase\\Repo\\LinkedData\\EntityDataSerializationService->rdfSerialize(Wikibase\\EntityRevision, NULL, array, Wikibase\\Rdf\\RdfBuilder, NULL)\n#4 /srv/mediawiki/php-1.26wmf19/extensions/Wikidata/extensions/Wikibase/repo/includes/LinkedData/EntityDataRequestHandler.php(454): Wikibase\\Repo\\LinkedData\\EntityDataSerializationService->getSerializedData(string, Wikibase\\EntityRevision, NULL, array, NULL)\n#5 /srv/mediawiki/php-1.26wmf19/extensions/Wikidata/extensions/Wikibase/repo/includes/LinkedData/EntityDataRequestHandler.php(244): Wikibase\\Repo\\LinkedData\\EntityDataRequestHandler->showData(WebRequest, OutputPage, string, Wikibase\\DataModel\\Entity\\ItemId, integer)\n#6 /srv/mediawiki/php-1.26wmf19/extensions/Wikidata/extensions/Wikibase/repo/includes/specials/SpecialEntityData.php(159): Wikibase\\Repo\\LinkedData\\EntityDataRequestHandler->handleRequest(string, WebRequest, OutputPage)\n#7 /srv/mediawiki/php-1.26wmf19/includes/specialpage/SpecialPage.php(384): Wikibase\\Repo\\Specials\\SpecialEntityData->execute(string)\n#8 /srv/mediawiki/php-1.26wmf19/includes/specialpage/SpecialPageFactory.php(553): SpecialPage->run(string)\n#9 /srv/mediawiki/php-1.26wmf19/includes/MediaWiki.php(249): SpecialPageFactory::executePath(Title, RequestContext)\n#10 /srv/mediawiki/php-1.26wmf19/includes/MediaWiki.php(677): MediaWiki->performRequest()\n#11 /srv/mediawiki/php-1.26wmf19/includes/MediaWiki.php(474): MediaWiki->main()\n#12 /srv/mediawiki/php-1.26wmf19/index.php(41): MediaWiki->run()\n#13 /srv/mediawiki/w/index.php(3): include(string)\n#14 {main}\n"}