diff --git a/includes/Html.php b/includes/Html.php
index 1f1867aa592..397550731a4 100644
--- a/includes/Html.php
+++ b/includes/Html.php
@@ -594,7 +594,7 @@ class Html {
 		$attrs = [];
 		if ( $nonce !== null ) {
 			$attrs['nonce'] = $nonce;
-		} elseif ( ContentSecurityPolicy::isNonceRequired( RequestContext::getMain()->getConfig() ) ) {
+		} elseif ( ContentSecurityPolicy::isNonceRequired( MediaWikiServices::getInstance()->getMainConfig() ) ) {
 			wfWarn( "no nonce set on script. CSP will break it" );
 		}
 
@@ -618,7 +618,7 @@ class Html {
 		$attrs = [ 'src' => $url ];
 		if ( $nonce !== null ) {
 			$attrs['nonce'] = $nonce;
-		} elseif ( ContentSecurityPolicy::isNonceRequired( RequestContext::getMain()->getConfig() ) ) {
+		} elseif ( ContentSecurityPolicy::isNonceRequired( MediaWikiServices::getInstance()->getMainConfig() ) ) {
 			wfWarn( "no nonce set on script. CSP will break it" );
 		}
 
diff --git a/includes/block/AbstractBlock.php b/includes/block/AbstractBlock.php
index ffa2ab9cd6b..8bc0cbd2afb 100644
--- a/includes/block/AbstractBlock.php
+++ b/includes/block/AbstractBlock.php
@@ -277,8 +277,8 @@ abstract class AbstractBlock implements Block {
 	 *  unsure (e.g. unrecognized right or unset property)
 	 */
 	public function appliesToRight( $right ) {
-		$config = RequestContext::getMain()->getConfig();
-		$blockDisablesLogin = $config->get( MainConfigNames::BlockDisablesLogin );
+		$blockDisablesLogin = MediaWikiServices::getInstance()->getMainConfig()
+			->get( MainConfigNames::BlockDisablesLogin );
 
 		$res = null;
 		switch ( $right ) {
@@ -498,8 +498,9 @@ abstract class AbstractBlock implements Block {
 
 		// This is a type of block which uses the ipb_allow_usertalk
 		// flag. The flag can still be overridden by global configs.
-		$config = RequestContext::getMain()->getConfig();
-		if ( !$config->get( MainConfigNames::BlockAllowsUTEdit ) ) {
+		if ( !MediaWikiServices::getInstance()->getMainConfig()
+			->get( MainConfigNames::BlockAllowsUTEdit )
+		) {
 			return true;
 		}
 		return !$this->isUsertalkEditAllowed();
diff --git a/includes/jobqueue/jobs/CategoryMembershipChangeJob.php b/includes/jobqueue/jobs/CategoryMembershipChangeJob.php
index 7cff262cf12..e3e6c2c742c 100644
--- a/includes/jobqueue/jobs/CategoryMembershipChangeJob.php
+++ b/includes/jobqueue/jobs/CategoryMembershipChangeJob.php
@@ -185,7 +185,6 @@ class CategoryMembershipChangeJob extends Job {
 	protected function notifyUpdatesForRevision(
 		LBFactory $lbFactory, WikiPage $page, RevisionRecord $newRev
 	) {
-		$config = RequestContext::getMain()->getConfig();
 		$title = $page->getTitle();
 
 		// Get the new revision
@@ -216,7 +215,7 @@ class CategoryMembershipChangeJob extends Job {
 		$catMembChange = new CategoryMembershipChange( $title, $blc, $newRev );
 		$catMembChange->checkTemplateLinks();
 
-		$batchSize = $config->get( MainConfigNames::UpdateRowsPerQuery );
+		$batchSize = $services->getMainConfig()->get( MainConfigNames::UpdateRowsPerQuery );
 		$insertCount = 0;
 
 		foreach ( $categoryInserts as $categoryName ) {
diff --git a/includes/page/WikiPage.php b/includes/page/WikiPage.php
index 93c160374f3..3371436b513 100644
--- a/includes/page/WikiPage.php
+++ b/includes/page/WikiPage.php
@@ -3191,7 +3191,7 @@ class WikiPage implements Page, IDBAccessObject, PageRecord {
 			return;
 		}
 
-		$config = RequestContext::getMain()->getConfig();
+		$config = MediaWikiServices::getInstance()->getMainConfig();
 
 		$params = [
 			'isOpportunistic' => true,
@@ -3216,7 +3216,8 @@ class WikiPage implements Page, IDBAccessObject, PageRecord {
 				RefreshLinksJob::newPrioritized( $this->mTitle, $params )
 			);
 		} elseif ( !$config->get( MainConfigNames::MiserMode ) &&
-		$parserOutput->hasReducedExpiry() ) {
+			$parserOutput->hasReducedExpiry()
+		) {
 			// Assume the output contains "dynamic" time/random based magic words.
 			// Only update pages that expired due to dynamic content and NOT due to edits
 			// to referenced templates/files. When the cache expires due to dynamic content,
diff --git a/includes/session/PHPSessionHandler.php b/includes/session/PHPSessionHandler.php
index c103e1adc7a..94136be8e2e 100644
--- a/includes/session/PHPSessionHandler.php
+++ b/includes/session/PHPSessionHandler.php
@@ -25,6 +25,7 @@ namespace MediaWiki\Session;
 
 use BagOStuff;
 use MediaWiki\MainConfigNames;
+use MediaWiki\MediaWikiServices;
 use Psr\Log\LoggerInterface;
 use Psr\Log\NullLogger;
 use Wikimedia\AtEase\AtEase;
@@ -58,7 +59,7 @@ class PHPSessionHandler implements \SessionHandlerInterface {
 
 	protected function __construct( SessionManager $manager ) {
 		$this->setEnableFlags(
-			\RequestContext::getMain()->getConfig()->get( MainConfigNames::PHPSessionHandling )
+			MediaWikiServices::getInstance()->getMainConfig()->get( MainConfigNames::PHPSessionHandling )
 		);
 		$manager->setupPHPSessionHandler( $this );
 	}
diff --git a/includes/session/SessionBackend.php b/includes/session/SessionBackend.php
index e6c32cde4e2..f5ff5f3ab78 100644
--- a/includes/session/SessionBackend.php
+++ b/includes/session/SessionBackend.php
@@ -156,7 +156,8 @@ final class SessionBackend {
 		SessionId $id, SessionInfo $info, CachedBagOStuff $store, LoggerInterface $logger,
 		HookContainer $hookContainer, $lifetime
 	) {
-		$phpSessionHandling = \RequestContext::getMain()->getConfig()->get( MainConfigNames::PHPSessionHandling );
+		$phpSessionHandling = MediaWikiServices::getInstance()->getMainConfig()
+			->get( MainConfigNames::PHPSessionHandling );
 		$this->usePhpSessionHandling = $phpSessionHandling !== 'disable';
 
 		if ( $info->getUserInfo() && !$info->getUserInfo()->isVerified() ) {
diff --git a/tests/phpunit/includes/ContentSecurityPolicyTest.php b/tests/phpunit/includes/ContentSecurityPolicyTest.php
index 28a1b370812..cfce3a45acc 100644
--- a/tests/phpunit/includes/ContentSecurityPolicyTest.php
+++ b/tests/phpunit/includes/ContentSecurityPolicyTest.php
@@ -370,7 +370,7 @@ class ContentSecurityPolicyTest extends MediaWikiIntegrationTestCase {
 	public function testCSPIsEnabled( $main, $reportOnly, $expected ) {
 		$this->setMwGlobals( 'wgCSPReportOnlyHeader', $reportOnly );
 		$this->setMwGlobals( 'wgCSPHeader', $main );
-		$res = ContentSecurityPolicy::isNonceRequired( RequestContext::getMain()->getConfig() );
+		$res = ContentSecurityPolicy::isNonceRequired( $this->getServiceContainer()->getMainConfig() );
 		$this->assertSame( $expected, $res );
 	}
 
diff --git a/tests/phpunit/includes/ResourceLoader/FileModuleTest.php b/tests/phpunit/includes/ResourceLoader/FileModuleTest.php
index 06b9c006449..92fc122317b 100644
--- a/tests/phpunit/includes/ResourceLoader/FileModuleTest.php
+++ b/tests/phpunit/includes/ResourceLoader/FileModuleTest.php
@@ -9,7 +9,6 @@ use MediaWiki\ResourceLoader\FileModule;
 use MediaWiki\ResourceLoader\FilePath;
 use MediaWiki\ResourceLoader\ResourceLoader;
 use Psr\Container\ContainerInterface;
-use RequestContext;
 use ResourceLoaderFileTestModule;
 use ResourceLoaderTestCase;
 use RuntimeException;
@@ -640,7 +639,7 @@ class FileModuleTest extends ResourceLoaderTestCase {
 		$nosemiScript = file_get_contents( "$basePath/script-nosemi.js" );
 		$vueComponentDebug = trim( file_get_contents( "$basePath/vue-component-output-debug.js.txt" ) );
 		$vueComponentNonDebug = trim( file_get_contents( "$basePath/vue-component-output-nondebug.js.txt" ) );
-		$config = RequestContext::getMain()->getConfig();
+		$config = \MediaWiki\MediaWikiServices::getInstance()->getMainConfig();
 		return [
 			[
 				$base + [
diff --git a/tests/phpunit/includes/auth/ConfirmLinkSecondaryAuthenticationProviderTest.php b/tests/phpunit/includes/auth/ConfirmLinkSecondaryAuthenticationProviderTest.php
index 33b384b9686..9aa9beb9c75 100644
--- a/tests/phpunit/includes/auth/ConfirmLinkSecondaryAuthenticationProviderTest.php
+++ b/tests/phpunit/includes/auth/ConfirmLinkSecondaryAuthenticationProviderTest.php
@@ -141,7 +141,7 @@ class ConfirmLinkSecondaryAuthenticationProviderTest extends \MediaWikiIntegrati
 			->onlyMethods( [ 'allowsAuthenticationDataChange' ] )
 			->setConstructorArgs( [
 				$request,
-				\RequestContext::getMain()->getConfig(),
+				$mwServices->getMainConfig(),
 				$mwServices->getObjectFactory(),
 				$mwServices->getHookContainer(),
 				$mwServices->getReadOnlyMode(),
diff --git a/tests/phpunit/includes/session/BotPasswordSessionProviderTest.php b/tests/phpunit/includes/session/BotPasswordSessionProviderTest.php
index 1af7d2c1b82..cb6c1a80214 100644
--- a/tests/phpunit/includes/session/BotPasswordSessionProviderTest.php
+++ b/tests/phpunit/includes/session/BotPasswordSessionProviderTest.php
@@ -5,7 +5,6 @@ namespace MediaWiki\Session;
 use MediaWikiIntegrationTestCase;
 use MultiConfig;
 use Psr\Log\LogLevel;
-use RequestContext;
 use Wikimedia\TestingAccessWrapper;
 
 /**
@@ -45,7 +44,7 @@ class BotPasswordSessionProviderTest extends MediaWikiIntegrationTestCase {
 			] );
 		}
 		$manager = new SessionManager( [
-			'config' => new MultiConfig( [ $this->config, RequestContext::getMain()->getConfig() ] ),
+			'config' => new MultiConfig( [ $this->config, $this->getServiceContainer()->getMainConfig() ] ),
 			'logger' => new \Psr\Log\NullLogger,
 			'store' => new TestBagOStuff,
 		] );
diff --git a/tests/phpunit/includes/session/SessionManagerTest.php b/tests/phpunit/includes/session/SessionManagerTest.php
index 3a9e074e826..bd3271acd0c 100644
--- a/tests/phpunit/includes/session/SessionManagerTest.php
+++ b/tests/phpunit/includes/session/SessionManagerTest.php
@@ -122,7 +122,7 @@ class SessionManagerTest extends MediaWikiIntegrationTestCase {
 		$this->assertSame( $this->store, $manager->store );
 
 		$manager = TestingAccessWrapper::newFromObject( new SessionManager() );
-		$this->assertSame( \RequestContext::getMain()->getConfig(), $manager->config );
+		$this->assertSame( $this->getServiceContainer()->getMainConfig(), $manager->config );
 
 		$manager = TestingAccessWrapper::newFromObject( new SessionManager( [
 			'config' => $this->config,
diff --git a/tests/phpunit/includes/session/TestBagOStuff.php b/tests/phpunit/includes/session/TestBagOStuff.php
index 2f6f025be5f..bbe2b2de408 100644
--- a/tests/phpunit/includes/session/TestBagOStuff.php
+++ b/tests/phpunit/includes/session/TestBagOStuff.php
@@ -4,7 +4,7 @@ namespace MediaWiki\Session;
 
 use CachedBagOStuff;
 use HashBagOStuff;
-use RequestContext;
+use MediaWiki\MediaWikiServices;
 
 /**
  * BagOStuff with utility functions for MediaWiki\\Session\\* testing
@@ -55,7 +55,7 @@ class TestBagOStuff extends CachedBagOStuff {
 	 * @param array|mixed $blob Session metadata and data
 	 */
 	public function setRawSession( $id, $blob ) {
-		$expiry = RequestContext::getMain()->getConfig()->get( 'ObjectCacheSessionExpiry' );
+		$expiry = MediaWikiServices::getInstance()->getMainConfig()->get( 'ObjectCacheSessionExpiry' );
 		$this->set( $this->makeKey( 'MWSession', $id ), $blob, $expiry );
 	}
 
diff --git a/tests/phpunit/includes/user/BotPasswordTest.php b/tests/phpunit/includes/user/BotPasswordTest.php
index 19986ebcd9a..00df1a99586 100644
--- a/tests/phpunit/includes/user/BotPasswordTest.php
+++ b/tests/phpunit/includes/user/BotPasswordTest.php
@@ -277,7 +277,7 @@ class BotPasswordTest extends MediaWikiIntegrationTestCase {
 		ScopedCallback::consume( $reset );
 
 		// Now configure BotPasswordSessionProvider for further tests...
-		$mainConfig = RequestContext::getMain()->getConfig();
+		$mainConfig = $this->getServiceContainer()->getMainConfig();
 		$config = new HashConfig( [
 			'SessionProviders' => $mainConfig->get( 'SessionProviders' ) + [
 				MediaWiki\Session\BotPasswordSessionProvider::class => [
@@ -288,7 +288,7 @@ class BotPasswordTest extends MediaWikiIntegrationTestCase {
 			],
 		] );
 		$manager = new SessionManager( [
-			'config' => new MultiConfig( [ $config, RequestContext::getMain()->getConfig() ] ),
+			'config' => new MultiConfig( [ $config, $mainConfig ] ),
 			'logger' => new Psr\Log\NullLogger,
 			'store' => new EmptyBagOStuff,
 		] );
diff --git a/tests/phpunit/structure/ApiStructureTest.php b/tests/phpunit/structure/ApiStructureTest.php
index 3a38362c447..fab10f761fa 100644
--- a/tests/phpunit/structure/ApiStructureTest.php
+++ b/tests/phpunit/structure/ApiStructureTest.php
@@ -69,7 +69,7 @@ class ApiStructureTest extends MediaWikiIntegrationTestCase {
 		// Set configuration variables
 		$main->getContext()->setConfig( new MultiConfig( [
 			new HashConfig( $globals ),
-			RequestContext::getMain()->getConfig(),
+			$this->getServiceContainer()->getMainConfig(),
 		] ) );
 		foreach ( $globals as $k => $v ) {
 			$this->setMwGlobals( "wg$k", $v );