We have an Chrome extension that works on certain areas of Facebook, Facebook has made recent interface changes that we need to modify our extension to compensate. You will be manipulating DOM objects in a Facebook session window. We have a working extension and licensing/payment gateway already.
Our current extension and a full technical brief is available to the winning bidder. No upfront payments, successful completion of project after testing will release payments.
This should only take a few hours based on my experiences working with the original developers of my extension, bid accordingly.
Good luck