In a previous post, we showed you the CSS necessary to make custom Share link in an FBML app or application tab. Since FBML is being deprecated, this obviously won’t work anymore.
In short – you can’t. Or at least not if you want to be PCI compliant. In order to pass a user’s personal information through a secure encrypted channel, you will need to collect that data on an IFRAME application page. No two ways about it. Here’s why: