Sync posts, subscribed threads, ignored users, etc.; no personal information (such as your PMs) is accessible to this extension.
GitHub: http://github.com/cedivad/bitcointa.lk/tree/master/chrome
The extension has limited access to your Bitcointalk.org account:
1) It can't access your personal messages or other private details. It will just alert you that you have unread PMs on Bitcointalk.org in case.
2) It can post, edit and delete messages on Bitcointalk.org using the account you are logged in with.
3) It can import your ignored list, signature, subscribed threads and forums.