Make Facebook publish dialog full screen

We have a Windows Phone app that invokes a browser to publish a post on the user's account. The problem is that the Facebook dialogs appear too small in the browser window, not full screen or even close. The usar has to zoom in a lot just to be able to read what the dialog says.

Also, the dialog stretches vertically to fill the browser window.

We're using the JS SDK.

Is there any way to make the dialog just show it's regular square-ish dimensions and fill the browser horizontally?