diff --git a/plugins/css-blank-pseudo/CHANGELOG.md b/plugins/css-blank-pseudo/CHANGELOG.md
index 9b4e8b101..64d29e6a2 100644
--- a/plugins/css-blank-pseudo/CHANGELOG.md
+++ b/plugins/css-blank-pseudo/CHANGELOG.md
@@ -1,5 +1,9 @@
 # Changes to CSS Blank Pseudo
 
+### Unreleased
+
+- Fix: assign global browser polyfill to `window`, `self` or a blank object.
+
 ### 4.1.0 (July 30, 2022)
 
 - Added: `disablePolyfillReadyClass` plugin option to prevent `.js-blank-pseudo` from being added.
diff --git a/plugins/css-blank-pseudo/src/browser-global.js b/plugins/css-blank-pseudo/src/browser-global.js
index e21c7bf19..5e307d8c7 100644
--- a/plugins/css-blank-pseudo/src/browser-global.js
+++ b/plugins/css-blank-pseudo/src/browser-global.js
@@ -1,3 +1,6 @@
-/* global self */
+/* global self,window */
 import { default as cssBlankPseudoInit } from './browser';
-self.cssBlankPseudoInit = cssBlankPseudoInit;
+
+(function (global) {
+	global.cssBlankPseudoInit = cssBlankPseudoInit;
+}('object' === typeof window && window || 'object' === typeof self && self || {}));
diff --git a/plugins/css-has-pseudo/CHANGELOG.md b/plugins/css-has-pseudo/CHANGELOG.md
index f71c546c9..24af98029 100644
--- a/plugins/css-has-pseudo/CHANGELOG.md
+++ b/plugins/css-has-pseudo/CHANGELOG.md
@@ -1,5 +1,9 @@
 # Changes to CSS Has Pseudo
 
+### Unreleased
+
+- Fix: assign global browser polyfill to `window`, `self` or a blank object.
+
 ### 4.0.0 (July 8, 2022)
 
 [Read the full changelog](https://github.com/csstools/postcss-plugins/wiki/PostCSS-Preset-Env-8)
diff --git a/plugins/css-has-pseudo/src/browser-global.js b/plugins/css-has-pseudo/src/browser-global.js
index c2abec111..3cba9e690 100644
--- a/plugins/css-has-pseudo/src/browser-global.js
+++ b/plugins/css-has-pseudo/src/browser-global.js
@@ -1,3 +1,6 @@
-/* global self */
+/* global self,window */
 import { default as cssHasPseudo } from './browser';
-self.cssHasPseudo = cssHasPseudo;
+
+(function (global) {
+	global.cssHasPseudo = cssHasPseudo;
+}('object' === typeof window && window || 'object' === typeof self && self || {}));
diff --git a/plugins/css-prefers-color-scheme/CHANGELOG.md b/plugins/css-prefers-color-scheme/CHANGELOG.md
index 27602cfd1..6a1ff983e 100644
--- a/plugins/css-prefers-color-scheme/CHANGELOG.md
+++ b/plugins/css-prefers-color-scheme/CHANGELOG.md
@@ -1,5 +1,9 @@
 # Changes to Prefers Color Scheme
 
+### Unreleased
+
+- Fix: assign global browser polyfill to `window`, `self` or a blank object.
+
 ### 7.0.0 (July 8, 2022)
 
 [Read the full changelog](https://github.com/csstools/postcss-plugins/wiki/PostCSS-Preset-Env-8)
diff --git a/plugins/css-prefers-color-scheme/src/browser-global.js b/plugins/css-prefers-color-scheme/src/browser-global.js
index 10e751c01..947c5f36a 100644
--- a/plugins/css-prefers-color-scheme/src/browser-global.js
+++ b/plugins/css-prefers-color-scheme/src/browser-global.js
@@ -1,3 +1,6 @@
-/* global self */
+/* global self,window */
 import { default as prefersColorSchemeInit } from './browser';
-self.prefersColorSchemeInit = prefersColorSchemeInit;
+
+(function (global) {
+	global.prefersColorSchemeInit = prefersColorSchemeInit;
+}('object' === typeof window && window || 'object' === typeof self && self || {}));
diff --git a/plugins/postcss-focus-within/CHANGELOG.md b/plugins/postcss-focus-within/CHANGELOG.md
index 50d276754..5923dc324 100644
--- a/plugins/postcss-focus-within/CHANGELOG.md
+++ b/plugins/postcss-focus-within/CHANGELOG.md
@@ -1,5 +1,9 @@
 # Changes to PostCSS Focus Within
 
+### Unreleased
+
+- Fix: assign global browser polyfill to `window`, `self` or a blank object.
+
 ### 6.1.0 (July 30, 2022)
 
 - Added: `disablePolyfillReadyClass` plugin option to prevent `.js-focus-within` from being added.
diff --git a/plugins/postcss-focus-within/src/browser-global.js b/plugins/postcss-focus-within/src/browser-global.js
index 7c6d41bd7..2a45d68ed 100644
--- a/plugins/postcss-focus-within/src/browser-global.js
+++ b/plugins/postcss-focus-within/src/browser-global.js
@@ -1,3 +1,6 @@
-/* global self */
+/* global self,window */
 import { default as focusWithinInit } from './browser';
-self.focusWithinInit = focusWithinInit;
+
+(function (global) {
+	global.focusWithinInit = focusWithinInit;
+}('object' === typeof window && window || 'object' === typeof self && self || {}));