Some program (or extension) tried to access function(s) of Semantic MediaWiki without being correctly enabled.
To use Semantic MediaWiki or functions of it, it is necessary to add enableSemantics to your LocalSetting.php which will ensure required variables and parameters are setup before programs can continue to work and make use of it.
Please have a look at the enableSemantics help page for further assistance.
The follwing stack trace may indicate which program (or extension) tried to access Semantic MediaWiki or some of its functions.
#0 /opt/mediawiki/core/extensions/SemanticMediaWiki/src/Connection/ConnectionManager.php(42): SMW\Connection\ConnectionManager->isConnectable()
#1 /opt/mediawiki/core/extensions/SemanticMediaWiki/src/Store.php(598): SMW\Connection\ConnectionManager->getConnection('mw.db')
#2 /opt/mediawiki/core/extensions/SemanticMediaWiki/src/SQLStore/SQLStore.php(655): SMW\Store->getConnection('mw.db')
#3 /opt/mediawiki/core/extensions/SemanticMediaWiki/src/SQLStore/SQLStoreFactory.php(410): SMW\SQLStore\SQLStore->getConnection('mw.db')
#4 /opt/mediawiki/core/extensions/SemanticMediaWiki/src/SQLStore/EntityStore/EntityIdManager.php(979): SMW\SQLStore\SQLStoreFactory->newPropertyTableHashes(Object(SMW\SQLStore\EntityStore\IdCacheManager))
#5 /opt/mediawiki/core/extensions/SemanticMediaWiki/src/SQLStore/EntityStore/EntityIdManager.php(139): SMW\SQLStore\EntityStore\EntityIdManager->initCache()
#6 /opt/mediawiki/core/extensions/SemanticMediaWiki/src/SQLStore/SQLStoreFactory.php(134): SMW\SQLStore\EntityStore\EntityIdManager->__construct(Object(SMW\SQLStore\SQLStore), Object(SMW\SQLStore\SQLStoreFactory))
#7 /opt/mediawiki/core/extensions/SemanticMediaWiki/src/SQLStore/SQLStore.php(168): SMW\SQLStore\SQLStoreFactory->newEntityIdManager()
#8 /opt/mediawiki/core/extensions/SemanticMediaWiki/src/StoreFactory.php(61): SMW\SQLStore\SQLStore->__construct()
#9 /opt/mediawiki/core/extensions/SemanticMediaWiki/src/StoreFactory.php(42): SMW\StoreFactory::newFromClass('SMWSQLStore3')
#10 /opt/mediawiki/core/extensions/SemanticMediaWiki/src/Services/SharedServicesContainer.php(101): SMW\StoreFactory::getStore('SMWSQLStore3')
#11 [internal function]: SMW\Services\SharedServicesContainer->newStore(Object(Onoi\CallbackContainer\CallbackContainerBuilder), 'SMWSQLStore3')
#12 /opt/mediawiki/core/vendor/onoi/callback-container/src/CallbackContainerBuilder.php(260): call_user_func_array(Array, Array)
#13 /opt/mediawiki/core/vendor/onoi/callback-container/src/CallbackContainerBuilder.php(288): Onoi\CallbackContainer\CallbackContainerBuilder->getReturnValueFromCallbackHandlerFor('Store', Array)
#14 /opt/mediawiki/core/vendor/onoi/callback-container/src/CallbackContainerBuilder.php(195): Onoi\CallbackContainer\CallbackContainerBuilder->getReturnValueFromSingletonFor('Store', Array)
#15 /opt/mediawiki/core/extensions/SemanticMediaWiki/src/Services/ServicesFactory.php(228): Onoi\CallbackContainer\CallbackContainerBuilder->singleton('Store', NULL)
#16 /opt/mediawiki/core/extensions/SemanticBreadcrumbLinks/SemanticBreadcrumbLinks.php(118): SMW\Services\ServicesFactory->getStore()
#17 /opt/mediawiki/core/includes/Setup.php(905): {closure}()
#18 /opt/mediawiki/core/includes/WebStart.php(81): require_once('/opt/mediawiki/...')
#19 /opt/mediawiki/core/mw-config/index.php(36): require('/opt/mediawiki/...')
#20 {main}