An element locator that will wait for the specified number of seconds for an element to appear, rather than failing instantly if it's not present. This works by polling the UI on a regular basis. The element returned will be present on the DOM, but may not actually be visible: override {@link #isElementUsable(WebElement)} if this is important to you.
Because this class polls the interface on a regular basis, it is strongly recommended that users avoid locating elements by XPath.