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Backtrace:
#0 /var/www/html/mediawiki/includes/libs/rdbms/loadbalancer/LoadBalancer.php(934): Wikimedia\Rdbms\LoadBalancer->reportConnectionError() #1 /var/www/html/mediawiki/includes/libs/rdbms/loadbalancer/LoadBalancer.php(901): Wikimedia\Rdbms\LoadBalancer->getServerConnection() #2 /var/www/html/mediawiki/includes/libs/rdbms/loadbalancer/LoadBalancer.php(1046): Wikimedia\Rdbms\LoadBalancer->getConnection() #3 /var/www/html/mediawiki/includes/GlobalFunctions.php(2463): Wikimedia\Rdbms\LoadBalancer->getMaintenanceConnectionRef() #4 /var/www/html/mediawiki/extensions/Gadgets/includes/MediaWikiGadgetsDefinitionRepo.php(106): wfGetDB() #5 /var/www/html/mediawiki/includes/libs/objectcache/wancache/WANObjectCache.php(1529): MediaWikiGadgetsDefinitionRepo->{closure}() #6 /var/www/html/mediawiki/includes/libs/objectcache/wancache/WANObjectCache.php(1376): WANObjectCache->fetchOrRegenerate() #7 /var/www/html/mediawiki/extensions/Gadgets/includes/MediaWikiGadgetsDefinitionRepo.php(116): WANObjectCache->getWithSetCallback() #8 /var/www/html/mediawiki/extensions/Gadgets/includes/MediaWikiGadgetsDefinitionRepo.php(32): MediaWikiGadgetsDefinitionRepo->loadGadgets() #9 /var/www/html/mediawiki/extensions/Gadgets/includes/GadgetRepo.php(71): MediaWikiGadgetsDefinitionRepo->getGadgetIds() #10 /var/www/html/mediawiki/extensions/Gadgets/includes/GadgetHooks.php(114): GadgetRepo->getStructuredList() #11 /var/www/html/mediawiki/includes/HookContainer/HookContainer.php(329): GadgetHooks::userGetDefaultOptions() #12 /var/www/html/mediawiki/includes/HookContainer/HookContainer.php(132): MediaWiki\HookContainer\HookContainer->callLegacyHook() #13 /var/www/html/mediawiki/includes/HookContainer/HookRunner.php(4254): MediaWiki\HookContainer\HookContainer->run() #14 /var/www/html/mediawiki/includes/user/DefaultOptionsLookup.php(99): MediaWiki\HookContainer\HookRunner->onUserGetDefaultOptions() #15 /var/www/html/mediawiki/includes/user/UserOptionsManager.php(494): MediaWiki\User\DefaultOptionsLookup->getDefaultOptions() #16 /var/www/html/mediawiki/includes/user/UserOptionsManager.php(135): MediaWiki\User\UserOptionsManager->loadUserOptions() #17 /var/www/html/mediawiki/includes/user/User.php(2670): MediaWiki\User\UserOptionsManager->getOption() #18 /var/www/html/mediawiki/includes/context/RequestContext.php(355): User->getOption() #19 /var/www/html/mediawiki/includes/language/Message.php(723): RequestContext->getLanguage() #20 /var/www/html/mediawiki/includes/context/RequestContext.php(447): Message->setContext() #21 /var/www/html/mediawiki/includes/specialpage/SpecialPage.php(829): RequestContext->msg() #22 /var/www/html/mediawiki/includes/specialpage/SpecialPage.php(687): SpecialPage->msg() #23 /var/www/html/mediawiki/includes/specialpage/SpecialPage.php(575): SpecialPage->getDescription() #24 /var/www/html/mediawiki/includes/specials/SpecialContributions.php(41): SpecialPage->setHeaders() #25 /var/www/html/mediawiki/includes/specialpage/SpecialPage.php(600): SpecialContributions->execute() #26 /var/www/html/mediawiki/includes/specialpage/SpecialPageFactory.php(635): SpecialPage->run() #27 /var/www/html/mediawiki/includes/MediaWiki.php(307): MediaWiki\SpecialPage\SpecialPageFactory->executePath() #28 /var/www/html/mediawiki/includes/MediaWiki.php(945): MediaWiki->performRequest() #29 /var/www/html/mediawiki/includes/MediaWiki.php(548): MediaWiki->main() #30 /var/www/html/mediawiki/index.php(53): MediaWiki->run() #31 /var/www/html/mediawiki/index.php(46): wfIndexMain() #32 {main}