https://metacpan.org/module/Facebook::Graph::Authorize says I should visit a webpage and look for "Dialog form factors" there. There's no "Dialog form factors" there. So, where should I look?
Facebook is constantly changing their APIs. It appears that while they still support this API (because I'm still using it successfully), they must be trying to get people to use other stuff. I'm afraid you'll just have to read the Facebook developer documentation, or just go with Facebook::Graph blindly. I generally use "page" as the type. And that is almost certainly what you want if you're doing a web app.
This is no longer supported by Facebook so I've removed it in Facebook::Graph 1.1000