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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}