'Zooming out a specified element.
It prevents different elements being driven out of xvfb viewport
(which in Selenium>=2.50.1 prevents interaction with them).'

def zoom_out(self, times=3):

    html = self.driver.find_element(by.By.TAG_NAME, 'html')
    html.send_keys(keys.Keys.NULL)
    zoom_out_keys = ((keys.Keys.SUBTRACT,) * times)
    action_chains.ActionChains(self.driver).key_down(keys.Keys.CONTROL).send_keys(*zoom_out_keys).key_up(keys.Keys.CONTROL).perform()
