From b6217bd4a940039834a21120e6adcad1b99b0010 Mon Sep 17 00:00:00 2001
From: Lauri Eskola <lauri.eskola@acquia.com>
Date: Tue, 12 Jul 2022 16:16:42 +0300
Subject: [PATCH] Issue #3252587 by longwave, smustgrave, Chalk, borisson_,
 alexpott: Extend the $skip_protocol_filtering list of attributes to use
 Tailwind CSS classes with prefix ":"

---
 core/lib/Drupal/Component/Utility/Xss.php             | 1 +
 core/tests/Drupal/Tests/Component/Utility/XssTest.php | 4 ++--
 2 files changed, 3 insertions(+), 2 deletions(-)

diff --git a/core/lib/Drupal/Component/Utility/Xss.php b/core/lib/Drupal/Component/Utility/Xss.php
index 1f1690d11c7..6d461d3f020 100644
--- a/core/lib/Drupal/Component/Utility/Xss.php
+++ b/core/lib/Drupal/Component/Utility/Xss.php
@@ -237,6 +237,7 @@ class Xss {
               'alt',
               'rel',
               'property',
+              'class',
             ]);
 
             $working = $mode = 1;
diff --git a/core/tests/Drupal/Tests/Component/Utility/XssTest.php b/core/tests/Drupal/Tests/Component/Utility/XssTest.php
index d8ddc227cae..db5ee1d7b91 100644
--- a/core/tests/Drupal/Tests/Component/Utility/XssTest.php
+++ b/core/tests/Drupal/Tests/Component/Utility/XssTest.php
@@ -504,8 +504,8 @@ class XssTest extends TestCase {
   public function providerTestAttributes() {
     return [
       [
-        '<img src="http://example.com/foo.jpg" title="Example: title" alt="Example: alt">',
-        '<img src="http://example.com/foo.jpg" title="Example: title" alt="Example: alt">',
+        '<img src="http://example.com/foo.jpg" title="Example: title" alt="Example: alt" class="md:block">',
+        '<img src="http://example.com/foo.jpg" title="Example: title" alt="Example: alt" class="md:block">',
         'Image tag with alt and title attribute',
         ['img'],
       ],