Chrome Extension - Load popup whenever Facebook is visited?

I'm just starting on a Chrome extension. I want it to load a popup elemen开发者_开发知识库t whenever the browser loads a Facebook url.

Is this possible? And how? // ANSWERED.

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Okay, then.

Now, I now how to make an extension that drops down in a small window at the top right of the page beneath the extension icons. *But how can I create a new div anywhere on the web page, like this buzzgrowl extension:http://buzzgrowl.com/ *?

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Yep it's possible. You can trigger a popup in your javascript. Set it to work only on facebook.com.

You can also do javascript checking of the url via window.location.