diff --git a/src/wp-includes/html-api/class-wp-css-compound-selector-list.php b/src/wp-includes/html-api/class-wp-css-compound-selector-list.php
index 02a958e647ef1..a74ffe0f45fc9 100644
--- a/src/wp-includes/html-api/class-wp-css-compound-selector-list.php
+++ b/src/wp-includes/html-api/class-wp-css-compound-selector-list.php
@@ -83,7 +83,7 @@ class WP_CSS_Compound_Selector_List implements WP_CSS_HTML_Tag_Processor_Matcher
 	 * @param WP_HTML_Tag_Processor $processor The processor.
 	 * @return bool True if the processor's current position matches the selector.
 	 */
-	public function matches( WP_HTML_Tag_Processor $processor ): bool {
+	public function matches( $processor ): bool {
 		if ( $processor->get_token_type() !== '#tag' ) {
 			return false;
 		}