diff --git a/wp-admin/includes/network.php b/wp-admin/includes/network.php
index 9577172a80..fb3d8d2786 100644
--- a/wp-admin/includes/network.php
+++ b/wp-admin/includes/network.php
@@ -33,8 +33,9 @@ function network_domain_check() {
  * @return bool Whether subdomain installation is allowed
  */
 function allow_subdomain_install() {
-	$domain = preg_replace( '|https?://([^/]+)|', '$1', get_option( 'home' ) );
-	if ( parse_url( get_option( 'home' ), PHP_URL_PATH ) || 'localhost' === $domain || preg_match( '|^[0-9]+\.[0-9]+\.[0-9]+\.[0-9]+$|', $domain ) ) {
+	$home   = get_option( 'home' );
+	$domain = parse_url( $home, PHP_URL_HOST );
+	if ( parse_url( $home, PHP_URL_PATH ) || 'localhost' === $domain || preg_match( '|^[0-9]+\.[0-9]+\.[0-9]+\.[0-9]+$|', $domain ) ) {
 		return false;
 	}
 
diff --git a/wp-includes/version.php b/wp-includes/version.php
index 31e6a28e7d..0dbfda1589 100644
--- a/wp-includes/version.php
+++ b/wp-includes/version.php
@@ -16,7 +16,7 @@
  *
  * @global string $wp_version
  */
-$wp_version = '6.6-alpha-58124';
+$wp_version = '6.6-alpha-58125';
 
 /**
  * Holds the WordPress DB revision, increments when changes are made to the WordPress DB schema.