diff --git a/src/wp-includes/html-api/class-wp-html-processor.php b/src/wp-includes/html-api/class-wp-html-processor.php
index ec6bf7af5d553..cbfcbdecebcbc 100644
--- a/src/wp-includes/html-api/class-wp-html-processor.php
+++ b/src/wp-includes/html-api/class-wp-html-processor.php
@@ -588,7 +588,7 @@ public function is_tag_closer() {
 	 *
 	 * @return bool Whether the current token is virtual.
 	 */
-	public function is_virtual() {
+	private function is_virtual() {
 		return (
 			isset( $this->current_element->provenance ) &&
 			'virtual' === $this->current_element->provenance