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(Cannot access the database)
Backtrace:
#0 /var/www/mediawiki_shared/includes/libs/rdbms/loadbalancer/LoadBalancer.php(769): Wikimedia\Rdbms\LoadBalancer->reportConnectionError()
#1 /var/www/mediawiki_shared/includes/GlobalFunctions.php(2694): Wikimedia\Rdbms\LoadBalancer->getConnection()
#2 /var/www/mediawiki_shared/extensions/AbuseFilter/includes/AbuseFilterHooks.php(456): wfGetDB()
#3 /var/www/mediawiki_shared/includes/libs/objectcache/WANObjectCache.php(1277): AbuseFilterHooks::{closure}()
#4 /var/www/mediawiki_shared/includes/libs/objectcache/WANObjectCache.php(1150): WANObjectCache->doGetWithSetCallback()
#5 /var/www/mediawiki_shared/extensions/AbuseFilter/includes/AbuseFilterHooks.php(475): WANObjectCache->getWithSetCallback()
#6 /var/www/mediawiki_shared/extensions/AbuseFilter/includes/AbuseFilterHooks.php(485): AbuseFilterHooks::fetchAllTags()
#7 /var/www/mediawiki_shared/includes/Hooks.php(174): AbuseFilterHooks::onListDefinedTags()
#8 /var/www/mediawiki_shared/includes/Hooks.php(202): Hooks::callHook()
#9 /var/www/mediawiki_shared/includes/changetags/ChangeTags.php(1541): Hooks::run()
#10 /var/www/mediawiki_shared/includes/libs/objectcache/WANObjectCache.php(1277): ChangeTags::{closure}()
#11 /var/www/mediawiki_shared/includes/libs/objectcache/WANObjectCache.php(1150): WANObjectCache->doGetWithSetCallback()
#12 /var/www/mediawiki_shared/includes/changetags/ChangeTags.php(1547): WANObjectCache->getWithSetCallback()
#13 /var/www/mediawiki_shared/includes/changetags/ChangeTags.php(1460): ChangeTags::listSoftwareDefinedTags()
#14 /var/www/mediawiki_shared/includes/changetags/ChangeTags.php(875): ChangeTags::listDefinedTags()
#15 /var/www/mediawiki_shared/includes/actions/HistoryAction.php(189): ChangeTags::buildTagFilterSelector()
#16 /var/www/mediawiki_shared/includes/actions/FormlessAction.php(43): HistoryAction->onView()
#17 /var/www/mediawiki_shared/includes/MediaWiki.php(501): FormlessAction->show()
#18 /var/www/mediawiki_shared/includes/MediaWiki.php(294): MediaWiki->performAction()
#19 /var/www/mediawiki_shared/includes/MediaWiki.php(860): MediaWiki->performRequest()
#20 /var/www/mediawiki_shared/includes/MediaWiki.php(517): MediaWiki->main()
#21 /var/www/mediawiki_shared/index.php(42): MediaWiki->run()
#22 {main}