diff --git a/package.json b/package.json
index a9f3def95737..24b8c8026606 100644
--- a/package.json
+++ b/package.json
@@ -61,7 +61,7 @@
     "@mdn/browser-compat-data": "^5.2.35",
     "@mozilla/glean": "1.3.0",
     "@use-it/interval": "^1.0.0",
-    "@webref/css": "^5.4.4",
+    "@webref/css": "^6.5.6",
     "accept-language-parser": "^1.5.0",
     "async": "^3.2.4",
     "chalk": "^5.2.0",
diff --git a/yarn.lock b/yarn.lock
index d426249557e1..912a2c340b17 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -2802,10 +2802,10 @@
   resolved "https://registry.yarnpkg.com/@webpack-cli/serve/-/serve-2.0.1.tgz#34bdc31727a1889198855913db2f270ace6d7bf8"
   integrity sha512-0G7tNyS+yW8TdgHwZKlDWYXFA6OJQnoLCQvYKkQP0Q2X205PSQ6RNUj0M+1OB/9gRQaUZ/ccYfaxd0nhaWKfjw==
 
-"@webref/css@^5.4.4":
-  version "5.4.4"
-  resolved "https://registry.yarnpkg.com/@webref/css/-/css-5.4.4.tgz#91cd765acc1cd92587b2099adb5d2f09608a608c"
-  integrity sha512-x+WAreAVNfSaLWBux9y/9QTKMDpiUbcZZKh72JOFVtm7ZQqmi5/m4YlbYNCu+GjCvuMWOtgwiBx7qf7OvWWykA==
+"@webref/css@^6.5.6":
+  version "6.5.6"
+  resolved "https://registry.yarnpkg.com/@webref/css/-/css-6.5.6.tgz#474362042e77583c63d1c579dc679aa9b2049235"
+  integrity sha512-q6inW0qCLrUE9aypg3cv1S53jN6ZT+bBTaW7JWXcB6OgXuOzVyEfr+E4J63huq8gzOWUvJB/dp36j7dcOZkOyw==
 
 "@xtuc/ieee754@^1.2.0":
   version "1.2.0"