https://commons.wikimedia.org/wiki/Special:ListProperties gives:
[XDeQBQpAIDAAAEqtkLEAAADN] 2019-01-10 18:33:42: Fatal exception of type "Wikimedia\Assert\PostconditionException"
```name=message
Postcondition failed: Namespace for entity type property must be defined!
```
```name=stacktrace
#0 /srv/mediawiki/php-1.33.0-wmf.12/extensions/Wikibase/repo/includes/Content/EntityHandler.php(449): Wikimedia\Assert\Assert::postcondition(boolean, string)
#1 /srv/mediawiki/php-1.33.0-wmf.12/extensions/Wikibase/repo/includes/Content/EntityHandler.php(433): Wikibase\Repo\Content\EntityHandler->getEntityNamespace()
#2 /srv/mediawiki/php-1.33.0-wmf.12/extensions/Wikibase/repo/includes/Content/EntityContentFactory.php(120): Wikibase\Repo\Content\EntityHandler->getTitleForId(Wikibase\DataModel\Entity\PropertyId)
#3 /srv/mediawiki/php-1.33.0-wmf.12/extensions/Wikibase/repo/includes/Store/TypeDispatchingEntityTitleStoreLookup.php(44): Wikibase\Repo\Content\EntityContentFactory->getTitleForId(Wikibase\DataModel\Entity\PropertyId)
#4 /srv/mediawiki/php-1.33.0-wmf.12/extensions/Wikibase/repo/includes/Specials/SpecialListProperties.php(167): Wikibase\Repo\Store\TypeDispatchingEntityTitleStoreLookup->getTitleForId(Wikibase\DataModel\Entity\PropertyId)
#5 /srv/mediawiki/php-1.33.0-wmf.12/extensions/Wikibase/repo/includes/Specials/SpecialWikibaseQueryPage.php(164): Wikibase\Repo\Specials\SpecialListProperties->formatRow(Wikibase\DataModel\Entity\PropertyId)
#6 /srv/mediawiki/php-1.33.0-wmf.12/extensions/Wikibase/repo/includes/Specials/SpecialWikibaseQueryPage.php(144): Wikibase\Repo\Specials\SpecialWikibaseQueryPage->outputResults(array, integer, integer)
#7 /srv/mediawiki/php-1.33.0-wmf.12/extensions/Wikibase/repo/includes/Specials/SpecialListProperties.php(102): Wikibase\Repo\Specials\SpecialWikibaseQueryPage->showQuery()
#8 /srv/mediawiki/php-1.33.0-wmf.12/includes/specialpage/SpecialPage.php(569): Wikibase\Repo\Specials\SpecialListProperties->execute(NULL)
#9 /srv/mediawiki/php-1.33.0-wmf.12/includes/specialpage/SpecialPageFactory.php(558): SpecialPage->run(NULL)
#10 /srv/mediawiki/php-1.33.0-wmf.12/includes/MediaWiki.php(288): MediaWiki\Special\SpecialPageFactory->executePath(Title, RequestContext)
#11 /srv/mediawiki/php-1.33.0-wmf.12/includes/MediaWiki.php(862): MediaWiki->performRequest()
#12 /srv/mediawiki/php-1.33.0-wmf.12/includes/MediaWiki.php(517): MediaWiki->main()
#13 /srv/mediawiki/php-1.33.0-wmf.12/index.php(42): MediaWiki->run()
#14 /srv/mediawiki/w/index.php(3): include(string)
#15 {main}
```