diff --git a/lib/browser/api/system-preferences.ts b/lib/browser/api/system-preferences.ts
index 9ad72dec0ea24..bdc77c4dcd9c9 100644
--- a/lib/browser/api/system-preferences.ts
+++ b/lib/browser/api/system-preferences.ts
@@ -16,7 +16,7 @@ if ('getAppLevelAppearance' in systemPreferences) {
 }
 
 if ('getEffectiveAppearance' in systemPreferences) {
-  const nativeEAGetter = systemPreferences.getAppLevelAppearance;
+  const nativeEAGetter = systemPreferences.getEffectiveAppearance;
   Object.defineProperty(SystemPreferences.prototype, 'effectiveAppearance', {
     get: () => nativeEAGetter.call(systemPreferences)
   });