diff --git a/platform/common/vapi-background.js b/platform/common/vapi-background.js
index 0c4b0b46d..0d3cc584e 100644
--- a/platform/common/vapi-background.js
+++ b/platform/common/vapi-background.js
@@ -45,13 +45,6 @@ if ( vAPI.canWASM === false ) {
 
 vAPI.supportsUserStylesheets = vAPI.webextFlavor.soup.has('user_stylesheet');
 
-// The real actual webextFlavor value may not be set in stone, so listen
-// for possible future changes.
-window.addEventListener('webextFlavor', function() {
-    vAPI.supportsUserStylesheets =
-        vAPI.webextFlavor.soup.has('user_stylesheet');
-}, { once: true });
-
 /******************************************************************************/
 
 vAPI.app = {
diff --git a/platform/common/vapi-common.js b/platform/common/vapi-common.js
index 552642b7d..e9f00dc62 100644
--- a/platform/common/vapi-common.js
+++ b/platform/common/vapi-common.js
@@ -83,12 +83,9 @@ vAPI.webextFlavor = {
     // Synchronous -- order of tests is important
     const match = /\bChrom(?:e|ium)\/([\d.]+)/.exec(ua);
     if ( match !== null ) {
-        soup.add('chromium');
+        soup.add('chromium')
+            .add('user_stylesheet');
         flavor.major = parseInt(match[1], 10) || 0;
-        // https://github.com/gorhill/uBlock/issues/3588
-        if ( flavor.major >= 66 ) {
-            soup.add('user_stylesheet');
-        }
     }
 
     // Don't starve potential listeners