JavaScript is a programming language used to make websites interactive and dynamic. Features such as buttons that respond to ...

HTML radio buttons are like check boxes that are kept in herds. Radio buttons are organized into "families," and only one radio button in each family can be on at any given time. The main reason to ...

So, when the user clicks the “Continue with Facebook” button, the URL from the postMessage payload executes in the proxy iframe, which leads to the execution of the JavaScript on Facebook.com.