diff --git a/includes/CommentParser.php b/includes/CommentParser.php
index 748fe7297..78d672db6 100644
--- a/includes/CommentParser.php
+++ b/includes/CommentParser.php
@@ -566,15 +566,14 @@ class CommentParser {
 
 		$username = null;
 		$displayName = null;
-		$namespaceId = $title->getNamespace();
 		$mainText = $title->getText();
 
-		if ( $namespaceId === NS_USER || $namespaceId === NS_USER_TALK ) {
+		if ( $title->inNamespace( NS_USER ) || $title->inNamespace( NS_USER_TALK ) ) {
 			$username = $mainText;
 			if ( str_contains( $username, '/' ) ) {
 				return null;
 			}
-			if ( $namespaceId === NS_USER ) {
+			if ( $title->inNamespace( NS_USER ) ) {
 				// Use regex trim for consistency with JS implementation
 				$text = preg_replace( [ '/^[\s]+/u', '/[\s]+$/u' ], '', $link->textContent ?? '' );
 				// Record the display name if it has been customised beyond changing case
@@ -582,7 +581,7 @@ class CommentParser {
 					$displayName = $text;
 				}
 			}
-		} elseif ( $namespaceId === NS_SPECIAL ) {
+		} elseif ( $title->inNamespace( NS_SPECIAL ) ) {
 			$parts = explode( '/', $mainText );
 			if ( count( $parts ) === 2 && $parts[0] === $this->specialContributionsName ) {
 				// Normalize the username: users may link to their contributions with an unnormalized name
diff --git a/includes/Hooks/HookUtils.php b/includes/Hooks/HookUtils.php
index e911fb326..7a2631ceb 100644
--- a/includes/Hooks/HookUtils.php
+++ b/includes/Hooks/HookUtils.php
@@ -386,7 +386,7 @@ class HookUtils {
 				static::hasPagePropCached( $title, 'newsectionlink' ) &&
 				// excluding the main namespace, unless it has been configured for signatures
 				(
-					$title->getNamespace() !== NS_MAIN ||
+					!$title->inNamespace( NS_MAIN ) ||
 					$services->getNamespaceInfo()->wantSignatures( $title->getNamespace() )
 				)
 			);
@@ -595,7 +595,7 @@ class HookUtils {
 		$namespaceInfo = $services->getNamespaceInfo();
 		Assert::precondition( $namespaceInfo->isTalk( $talkPage->getNamespace() ), "Page is a talk page" );
 
-		if ( $talkPage->getNamespace() === NS_USER_TALK && !str_contains( $talkPage->getText(), '/' ) ) {
+		if ( $talkPage->inNamespace( NS_USER_TALK ) && !str_contains( $talkPage->getText(), '/' ) ) {
 			if ( $services->getUserNameUtils()->isIP( $talkPage->getText() ) ) {
 				return true;
 			}
diff --git a/includes/Hooks/PageHooks.php b/includes/Hooks/PageHooks.php
index 5f825bcb5..dc55c6c9c 100644
--- a/includes/Hooks/PageHooks.php
+++ b/includes/Hooks/PageHooks.php
@@ -438,7 +438,7 @@ class PageHooks implements
 		$descParams = [];
 		$buttonMsg = 'discussiontools-emptystate-button';
 		$title = $context->getTitle();
-		if ( $title->getNamespace() === NS_USER_TALK && !$title->isSubpage() ) {
+		if ( $title->inNamespace( NS_USER_TALK ) && !$title->isSubpage() ) {
 			// This is a user talk page
 			$isIP = $this->userNameUtils->isIP( $title->getText() );
 			$isTemp = $this->userNameUtils->isTemp( $title->getText() );
diff --git a/includes/ThreadItem/ContentCommentItem.php b/includes/ThreadItem/ContentCommentItem.php
index e90b426f1..bf59bdc13 100644
--- a/includes/ThreadItem/ContentCommentItem.php
+++ b/includes/ThreadItem/ContentCommentItem.php
@@ -135,7 +135,7 @@ class ContentCommentItem extends ContentThreadItem implements CommentItem {
 			if ( $href ) {
 				$siteConfig = MediaWikiServices::getInstance()->getMainConfig();
 				$title = Title::newFromText( CommentUtils::getTitleFromUrl( $href, $siteConfig ) );
-				if ( $title && $title->getNamespace() === NS_USER ) {
+				if ( $title && $title->inNamespace( NS_USER ) ) {
 					// TODO: Consider returning User objects
 					$users[] = $title;
 				}