Failure when creating a new environment from Patchdemo using the All preset bundle:
[80d546ceb230609473e3eaa4] [no req] Error: Interface 'Opis\JsonSchema\ISchemaLoader' not found Backtrace: from /var/www/html/w/extensions/WikiLambda/includes/Validation/YumYumYamlLoader.php(16) #0 /var/www/html/w/includes/AutoLoader.php(226): require_once() #1 [internal function]: AutoLoader::autoload() #2 /var/www/html/w/extensions/WikiLambda/includes/Validation/SchemaFactory.php(50): spl_autoload_call() #3 /var/www/html/w/extensions/WikiLambda/includes/Validation/ZObjectStructureValidator.php(40): MediaWiki\Extension\WikiLambda\Validation\SchemaFactory::getCanonicalFormFactory() #4 /var/www/html/w/extensions/WikiLambda/includes/ZObjectFactory.php(227): MediaWiki\Extension\WikiLambda\Validation\ZObjectStructureValidator::createCanonicalValidator() #5 /var/www/html/w/extensions/WikiLambda/includes/ZObjectFactory.php(129): MediaWiki\Extension\WikiLambda\ZObjectFactory::create() #6 /var/www/html/w/extensions/WikiLambda/includes/ZObjectContent.php(175): MediaWiki\Extension\WikiLambda\ZObjectFactory::createPersistentContent() #7 /var/www/html/w/extensions/WikiLambda/includes/ZObjectContent.php(188): MediaWiki\Extension\WikiLambda\ZObjectContent->validateContent() #8 /var/www/html/w/extensions/WikiLambda/includes/ZObjectContentHandler.php(553): MediaWiki\Extension\WikiLambda\ZObjectContent->isValid() #9 /var/www/html/w/includes/content/Transform/ContentTransformer.php(46): MediaWiki\Extension\WikiLambda\ZObjectContentHandler->preSaveTransform() #10 /var/www/html/w/includes/Storage/DerivedPageDataUpdater.php(941): MediaWiki\Content\Transform\ContentTransformer->preSaveTransform() #11 /var/www/html/w/includes/Storage/PageUpdater.php(339): MediaWiki\Storage\DerivedPageDataUpdater->prepareContent() #12 /var/www/html/w/includes/Storage/PageUpdater.php(883): MediaWiki\Storage\PageUpdater->prepareUpdate() #13 /var/www/html/w/extensions/WikiLambda/includes/Hooks.php(283): MediaWiki\Storage\PageUpdater->saveRevision() #14 /var/www/html/w/extensions/WikiLambda/includes/Hooks.php(178): MediaWiki\Extension\WikiLambda\Hooks::insertContentObject() #15 /var/www/html/w/includes/installer/DatabaseUpdater.php(595): MediaWiki\Extension\WikiLambda\Hooks::createInitialContent() #16 /var/www/html/w/includes/installer/DatabaseUpdater.php(552): MediaWiki\Installer\DatabaseUpdater->runUpdates() #17 /var/www/html/w/maintenance/update.php(195): MediaWiki\Installer\DatabaseUpdater->doUpdates() #18 /var/www/html/w/maintenance/includes/MaintenanceRunner.php(703): UpdateMediaWiki->execute() #19 /var/www/html/w/maintenance/doMaintenance.php(100): MediaWiki\Maintenance\MaintenanceRunner->run() #20 /var/www/html/w/maintenance/update.php(308): require_once(string) #21 {main}
Screenshot from a legacy deployment: