diff --git a/extension.json b/extension.json
index 698ecbb..f25cfb9 100644
--- a/extension.json
+++ b/extension.json
@@ -30,7 +30,7 @@
 		"GetPreferences": "Isekai\\OIDC\\IsekaiOIDCAuthHooks::onGetPreferences",
 		"SkinTemplateNavigation::Universal": "Isekai\\OIDC\\IsekaiOIDCAuthHooks::onSkinTemplateUniversalNavigation",
 		"ResourceLoaderGetConfigVars": "Isekai\\OIDC\\IsekaiOIDCAuthHooks::onResourceLoaderGetConfigVars",
-		"Isekai::GetUserAvatar": "Isekai\\OIDC\\IsekaiOIDCAuthHooks::onGetUserAvatar"
+		"Isekai::GetUsersAvatar": "Isekai\\OIDC\\IsekaiOIDCAuthHooks::onGetUsersAvatar"
 	},
 	"ExtensionMessagesFiles": {
 		"IsekaiOIDCAlias": "IsekaiOIDC.alias.php"
diff --git a/includes/ApiOIDCAvatar.php b/includes/ApiOIDCAvatar.php
index 06aa3eb..7d84ea4 100644
--- a/includes/ApiOIDCAvatar.php
+++ b/includes/ApiOIDCAvatar.php
@@ -38,12 +38,15 @@ class ApiOIDCAvatar extends ApiQueryBase {
 
         $size = $this->getParameter('size');
 
-        $avatarUrl = '';
+        $avatars = [];
 
         $hookContainer = $services->getHookContainer();
-        $hookContainer->run('Isekai::GetUserAvatar', [&$avatarUrl, $size, $user]);
+        $hookContainer->run('Isekai::GetUsersAvatar', [&$avatars, [$user], $size]);
 
-        if (empty($avatarUrl)) {
+        $avatarUrl = '';
+        if (isset($avatars[$user->getId()])) {
+            $avatarUrl = $avatars[$user->getId()];
+        } else {
             if (isset($wgIsekaiOIDC['defaultAvatarUrl'])) {
                 $avatarUrl = $wgIsekaiOIDC['defaultAvatarUrl'];
             } else {
diff --git a/includes/IsekaiOIDCAuth.php b/includes/IsekaiOIDCAuth.php
index 17a3ad5..4f5ae47 100644
--- a/includes/IsekaiOIDCAuth.php
+++ b/includes/IsekaiOIDCAuth.php
@@ -454,6 +454,28 @@ class IsekaiOIDCAuth extends AbstractPrimaryAuthenticationProvider {
 		}
 	}
 
+	public static function findOidcSubjectsByUserIds( array $userIds ) {
+		$dbr = MediaWikiServices::getInstance()->getDBLoadBalancer()->getMaintenanceConnectionRef( DB_REPLICA );
+		$rows = $dbr->select(
+			[
+				self::OIDC_TABLE
+			],
+			[
+				'oidc_user',
+				'oidc_subject'
+			],
+			[
+				'oidc_user' => $userIds
+			],
+			__METHOD__
+		);
+		$subjects = [];
+		foreach ( $rows as $row ) {
+			$subjects[$row->oidc_user] = $row->oidc_subject;
+		}
+		return $subjects;
+	}
+
 	private static function getPreferredUsername( $config, $oidc, $realname, $email ) {
 		if ( isset( $config['preferred_username'] ) ) {
 			wfDebugLog( self::LOG_TAG, 'Using ' . $config['preferred_username'] .
@@ -555,18 +577,19 @@ class IsekaiOIDCAuth extends AbstractPrimaryAuthenticationProvider {
 			$preferred_username = 'User';
 		}
 
-		if ( MediaWikiServices::getInstance()
-            ->getUserIdentityLookup()
-            ->getUserIdentityByName( $preferred_username ) ) {
+		$userIdentityLookup = MediaWikiServices::getInstance()->getUserIdentityLookup();
+		$userIdentity = $userIdentityLookup->getUserIdentityByName( $preferred_username );
+		if ( !$userIdentity || !$userIdentity->isRegistered() ) {
 
 			return $preferred_username;
 		}
 
 		$count = 1;
-		while ( MediaWikiServices::getInstance()
-            ->getUserIdentityLookup()
-            ->getUserIdentityByName( $preferred_username . $count ) ) {
-
+		while ( true ) {
+			$userIdentity = $userIdentityLookup->getUserIdentityByName( $preferred_username . $count );
+			if ( !$userIdentity || !$userIdentity->isRegistered() ) {
+				break;
+			}
 			$count ++;
 		}
 		return $preferred_username . $count;
diff --git a/includes/IsekaiOIDCAuthHooks.php b/includes/IsekaiOIDCAuthHooks.php
index ad39f61..3871c8c 100644
--- a/includes/IsekaiOIDCAuthHooks.php
+++ b/includes/IsekaiOIDCAuthHooks.php
@@ -171,33 +171,57 @@ class IsekaiOIDCAuthHooks {
 		return true;
 	}
 
-	public static function onGetUserAvatar(&$avatarUrl, $size, $user) {
+	/**
+	 * Get avatar url for users
+	 * @param array &$avatars
+	 * @param \User[] $users
+	 * @param int $size
+	 */
+	public static function onGetUsersAvatar(&$avatars, array $users, $size = 128) {
+		if (!is_array($avatars)) {
+			$avatars = [];
+		}
+
 		$services = MediaWikiServices::getInstance();
 		$config = $services->getMainConfig();
 		$wgIsekaiOIDC = $config->get('IsekaiOIDC');
 		
 		if (isset($wgIsekaiOIDC['avatarUrl'])) {
-			list($subject, $accessToken, $refreshToken) = IsekaiOIDCAuth::findOidcDataByUserId($user->getId());
-			$avatarFinded = false;
-			if ($subject) {
-				$avatarUrl = str_replace(['{openid}', '{username}'], [urlencode($subject), urlencode($user->getName())], $wgIsekaiOIDC['avatarUrl']);
-				$avatarFinded = true;
-			} else {
-				if (isset($wgIsekaiOIDC['defaultAvatarUrl'])) {
-					$avatarUrl = $wgIsekaiOIDC['defaultAvatarUrl'];
-					$avatarFinded = true;
+			$userIds = array_map(function($user) {
+				return $user->getId();
+			}, $users);
+
+			$subjects = IsekaiOIDCAuth::findOidcSubjectsByUserIds($userIds);
+
+			foreach ($users as $user) {
+				$subject = null;
+				if (isset($subjects[$user->getId()])) {
+					$subject = $subjects[$user->getId()];
 				}
-			}
 
-			if ($avatarFinded) {
-				if ($size <= 64) {
-					$avatarUrl = "$avatarUrl?size=md";
-				} else if ($size <= 128) {
-					$avatarUrl = "$avatarUrl?size=lg";
-				} else if ($size <= 256) {
-					$avatarUrl = "$avatarUrl?size=xl";
+				$avatarFinded = false;
+				if ($subject) {
+					$avatarUrl = str_replace(['{openid}', '{username}'], [urlencode($subject), urlencode($user->getName())], $wgIsekaiOIDC['avatarUrl']);
+					$avatarFinded = true;
 				} else {
-					$avatarUrl = "$avatarUrl?size=xxl";
+					if (isset($wgIsekaiOIDC['defaultAvatarUrl'])) {
+						$avatarUrl = $wgIsekaiOIDC['defaultAvatarUrl'];
+						$avatarFinded = true;
+					}
+				}
+
+				if ($avatarFinded) {
+					if ($size <= 64) {
+						$avatarUrl = "$avatarUrl?size=md";
+					} else if ($size <= 128) {
+						$avatarUrl = "$avatarUrl?size=lg";
+					} else if ($size <= 256) {
+						$avatarUrl = "$avatarUrl?size=xl";
+					} else {
+						$avatarUrl = "$avatarUrl?size=xxl";
+					}
+
+					$avatars[$user->getId()] = $avatarUrl;
 				}
 			}
 		}