Fixes #3
diff --git a/manifest.json b/manifest.json
index 10c4315..af381a9 100644
--- a/manifest.json
+++ b/manifest.json
@@ -18,7 +18,8 @@
     },
     {
       "matches": ["https://support.google.com/*/thread/*"],
-      "js": ["thread_inject.js"]
+      "js": ["thread_inject.js"],
+      "run_at": "document_end"
     }
   ],
   "permissions": [