diff --git a/wp-includes/SimplePie/src/IRI.php b/wp-includes/SimplePie/src/IRI.php
index 7fc538cd43..8d7e2923b1 100644
--- a/wp-includes/SimplePie/src/IRI.php
+++ b/wp-includes/SimplePie/src/IRI.php
@@ -170,7 +170,7 @@ class IRI
             $return = null;
         }
 
-        if ($return === null && isset($this->normalization[$this->scheme][$name])) {
+        if ($return === null && isset($this->scheme, $this->normalization[$this->scheme][$name])) {
             return $this->normalization[$this->scheme][$name];
         }
 
@@ -623,6 +623,10 @@ class IRI
      */
     protected function scheme_normalization()
     {
+        if ($this->scheme === null) {
+            return;
+        }
+
         if (isset($this->normalization[$this->scheme]['iuserinfo']) && $this->iuserinfo === $this->normalization[$this->scheme]['iuserinfo']) {
             $this->iuserinfo = null;
         }
diff --git a/wp-includes/version.php b/wp-includes/version.php
index cf7c9bed5f..9e67dca57a 100644
--- a/wp-includes/version.php
+++ b/wp-includes/version.php
@@ -16,7 +16,7 @@
  *
  * @global string $wp_version
  */
-$wp_version = '6.9-alpha-60946';
+$wp_version = '6.9-alpha-60947';
 
 /**
  * Holds the WordPress DB revision, increments when changes are made to the WordPress DB schema.