The button's location and size are properties of its DOM element.
You should be able to code a JavaScript "onsubmit" function that stores those values into hidden form fields so that they'll get posted to backing bean properties and available when the submit action method is invoked.
The secret of how to be miserable is to constantly expect things are going to happen the way that they are "supposed" to happen.
You can have faith, which carries the understanding that you may be disappointed. Then there's being a willfully-blind idiot, which virtually guarantees it.