diff --git a/extension/background.js b/extension/background.js
index 51d1d71..ad419ad 100644
--- a/extension/background.js
+++ b/extension/background.js
@@ -119,11 +119,15 @@ browser.storage.local.get(['overrides', 'accepted', 'installationId'], v => {
     overrides = v.overrides || {}
 
     var migration = overrides[MIGRATION] || 0;
-    var CURRENT_VERSION = 4;
+    var CURRENT_VERSION = 5;
     if(migration < CURRENT_VERSION){
 
         for(var key of Object.getOwnPropertyNames(overrides)){
             if(key.startsWith(':')) continue;
+            if(key.startsWith('facebook.com/a.')){
+                delete overrides[key];
+                continue;
+            }
             if(key != key.toLowerCase()){
                 var v = overrides[key];
                 delete overrides[key];
diff --git a/extension/content.js b/extension/content.js
index 3fca12b..3b30942 100644
--- a/extension/content.js
+++ b/extension/content.js
@@ -404,7 +404,7 @@ function getIdentifierInternal(urlstr) {
     if (isHostedOn(host, 'facebook.com')) {
         var s = getQuery(url.search);
         var p = url.pathname.replace('/pg/', '/');
-        return 'facebook.com/' + (s.story_fbid || s.set || s.story_fbid || s._ft_ || s.ft_id || s.id || takeFirstPathComponents(p, p.startsWith('/groups/') ? 2 : 1).substring(1));
+        return 'facebook.com/' + (s._ft_ || s.ft_id || s.id || takeFirstPathComponents(p, p.startsWith('/groups/') ? 2 : 1).substring(1));
     }
     if (isHostedOn(host, 'reddit.com')) {
         var pathname = url.pathname.replace('/u/', '/user/');