suggestion implemented return blank array

--- ./lib/private/User/Manager.php	2023-02-03 17:18:44.729561986 +0530

+++ ./lib/private/User/Manager-new.php	2023-02-09 21:41:35.339729765 +0530

@@ -705,6 +705,20 @@

+++ ./lib/private/User/Manager-new.php	2023-02-10 16:40:27.367230901 +0530

@@ -705,6 +705,48 @@

 	 * @since 9.1.0

 	 */

 	public function getByEmail($email) {

+		$uid=$email; // get first part of email if it contains alt domain, otherwise it is just $email

+		$mail_domain = $this->config->getSystemValue('mail_domain', '');

+		$alt_domain = $this->config->getSystemValue('alt_mail_domain', '');

+

+		$alt_domain_suffix ='';

+		$domain_found=1;

+

+		if (isset($mail_domain) && !empty($mail_domain)) {

+			$mail_domain_suffix ='@'  . $mail_domain;

+		}

+

+		if (isset($alt_domain) && !empty($alt_domain)) {

+			$alt_domain_suffix ='@'  . $alt_domain;

+		}

+

+		if (!empty($mail_domain_suffix) && stristr($email, $mail_domain_suffix) == FALSE) {

+			$domain_found=0;

+		}

+

+		if (!empty($alt_domain_suffix) && stristr($email, $alt_domain_suffix) == FALSE) {

+			$domain_found=0;

+		}

+

+		if($domain_found == 0){

+			return [];

+		}

+

+		if (!empty($alt_domain_suffix) && stristr($email, $alt_domain_suffix) !== FALSE) {

+			$uid = str_replace($alt_domain_suffix, '', $email);

+		}

+

+		if (!empty($alt_domain_suffix) && stristr($email, $alt_domain_suffix) !== FALSE) {

+			$uid = str_replace($alt_domain_suffix, '', $email);

+		}

+

+		if (!empty($alt_domain_suffix) && stristr($email, $alt_domain_suffix) !== FALSE) {

+			$uid = str_replace($alt_domain_suffix, '', $email);

+		}