```
        media_frame =  self.marionette.find_element('id', 'preview')
        scr_height = int(self.marionette.execute_script('return window.screen.height'))
        self.wait_for_condition(lambda m: (media_frame.location['y'] + media_frame.size['height']) == scr_height)
```
can you adapt that code somehow in a prettier way?
That 'rebases' the `y` location relative to the screen height so it will work properly on a larger screen device.