From 4639ff8920189480d0f39f8c2275277d18f73f9b Mon Sep 17 00:00:00 2001
From: Dennis Snell <dennis.snell@automattic.com>
Date: Fri, 12 Jan 2024 13:23:12 -0500
Subject: [PATCH] Remove early bailout of special elements. It's duplicated.

---
 .../html-api/class-wp-html-tag-processor.php  | 34 +++++++++----------
 1 file changed, 16 insertions(+), 18 deletions(-)

diff --git a/src/wp-includes/html-api/class-wp-html-tag-processor.php b/src/wp-includes/html-api/class-wp-html-tag-processor.php
index 5fbdcc28b1b9c..8f9e7b93e5c73 100644
--- a/src/wp-includes/html-api/class-wp-html-tag-processor.php
+++ b/src/wp-includes/html-api/class-wp-html-tag-processor.php
@@ -908,23 +908,6 @@ public function next_token() {
 		}
 
 		$tag_name = $this->get_tag();
-		if (
-			// Skips SCRIPT data.
-			'SCRIPT' !== $tag_name &&
-
-			// Skips RCDATA data.
-			'TEXTAREA' !== $tag_name &&
-			'TITLE' !== $tag_name &&
-
-			// Skips RAWTEXT data.
-			'IFRAME' !== $tag_name &&
-			'NOEMBED' !== $tag_name &&
-			'NOFRAMES' !== $tag_name &&
-			'STYLE' !== $tag_name &&
-			'XMP' !== $tag_name
-		) {
-			return true;
-		}
 
 		/*
 		 * Preserve the opening tag pointers, as these will be overwritten
@@ -938,7 +921,7 @@ public function next_token() {
 		$attributes           = $this->attributes;
 		$duplicate_attributes = $this->duplicate_attributes;
 
-		// Find the closing tag.
+		// Find the closing tag if necessary.
 		$found_closer = false;
 		switch ( $tag_name ) {
 			case 'SCRIPT':
@@ -950,6 +933,17 @@ public function next_token() {
 				$found_closer = $this->skip_rcdata( $tag_name );
 				break;
 
+			/*
+			 * In the browser this list would include the NOSCRIPT element,
+			 * but the Tag Processor is an environment with the scripting
+			 * flag disabled, meaning that it needs to descend into the
+			 * NOSCRIPT element to be able to properly process what will be
+			 * sent to a browser.
+			 *
+			 * Note that this rule makes HTML5 syntax incompatible with XML,
+			 * because the parsing of this token depends on client application.
+			 * The NOSCRIPT element cannot be represented in the XHTML syntax.
+			 */
 			case 'IFRAME':
 			case 'NOEMBED':
 			case 'NOFRAMES':
@@ -957,6 +951,10 @@ public function next_token() {
 			case 'XMP':
 				$found_closer = $this->skip_rawtext( $tag_name );
 				break;
+
+			// No other tags should be treated in their entirety here.
+			default:
+				return true;
 		}
 
 		if ( ! $found_closer ) {