diff --git a/platform/firefox/frameModule.js b/platform/firefox/frameModule.js
index cd513dc..9e1c444 100644
--- a/platform/firefox/frameModule.js
+++ b/platform/firefox/frameModule.js
@@ -55,11 +55,6 @@ const contentObserver = {
     cpMessageName: hostName + ':shouldLoad',
     ignoredPopups: new WeakMap(),
     uniqueSandboxId: 1,
-    subscriberTargets: {
-        'adblockplus.org': true,
-        'adblockplus.me': true,
-        'fanboy.co.nz': true
-    },
 
     get componentRegistrar() {
         return Components.manager.QueryInterface(Ci.nsIComponentRegistrar);
@@ -265,8 +260,8 @@ const contentObserver = {
         this.removeEventListener('mousedown', contObs.ignorePopup, true);
     },
 
-    observe: function(subject) {
-        let win = subject.defaultView;
+    observe: function(doc) {
+        let win = doc.defaultView;
 
         if ( !win ) {
             return;
@@ -294,33 +289,17 @@ const contentObserver = {
         lss(this.contentBaseURI + 'vapi-client.js', sandbox);
         lss(this.contentBaseURI + 'contentscript-start.js', sandbox);
 
-        let docReady = function(e) {
-            this.removeEventListener(e.type, docReady, true);
-            lss(contentObserver.contentBaseURI + 'contentscript-end.js', sandbox);
+        let docReady = (e) => {
+            let doc = e.target;
+            doc.removeEventListener(e.type, docReady, true);
+            lss(this.contentBaseURI + 'contentscript-end.js', sandbox);
+
+            if ( doc.querySelector('a[href^="abp:"]') ) {
+                lss(this.contentBaseURI + 'subscriber.js', sandbox);
+            }
         };
 
-        subject.addEventListener('DOMContentLoaded', docReady, true);
-
-/* Does not work, I do not know why
-
-        let docIdle = function(e) {
-            this.removeEventListener(e.type, docIdle);
-            lss(this.contentBaseURI + 'subscriber.js', sandbox);
-        };
-
-        var target = loc.host;
-        while ( target !== '' ) {
-            if ( this.subscriberTargets.hasOwnProperty(target) ) {
-                subject.addEventListener('load', docIdle);
-                break;
-            }
-            let pos = target.indexOf('.');
-            if ( pos === -1 ) {
-                break;
-            }
-            target = target.slice(pos + 1);
-        }
-*/
+        doc.addEventListener('DOMContentLoaded', docReady, true);
     }
 };