How do you create google chrome extensions?

Why aren't my google chrome extensions working?

• i downloaded the facebook 'poke all' button and when i try to use it, it isn't there. i went into 'settings', then 'tools', and then 'extensions' and it says: Facebook Poke All - Version: 1.6 Adds a 'Poke All' button to facebook Disable - Uninstall Allow in incognito but every time i try to use it, it doesn't work :( can someone help me and tell me what i'm doing wrong? thanks in advance x here is where i downloaded it from: https://chrome.google.com/extensions/detail/dbpnngnfdfaocafgegelojgegidbbhob some people are saying it works and others say it doesn't.

• Answer:

  I think facebook has changed the code of their site after that the script were last update.