diff --git a/src/ZenCommonUtils.mjs b/src/ZenCommonUtils.mjs
index 24bca5d..e2bd80f 100644
--- a/src/ZenCommonUtils.mjs
+++ b/src/ZenCommonUtils.mjs
@@ -42,6 +42,7 @@ class ZenMultiWindowFeature {
 
 class ZenDOMOperatedFeature {
   constructor() {
-    window.addEventListener('DOMContentLoaded', this.init.bind(this));
+    var initBound = this.init.bind(this);
+    window.addEventListener('DOMContentLoaded', initBound, { once: true });
   }
 }