So I\'m working with selenium firefox webdrivers in c# winform and I have this code below to get the handle of the popup that shows when you click on the \"webtraffic_popup_
If the lastly opened window is your target then simply do the following after the click
driver.SwitchTo().Window(driver.WindowHandles.ToList().Last());
EDIT
//You may need to go back to parent window to perform additional actions;
// to the new window
driver.SwitchTo().Window(driver.WindowHandles.ToList().Last());
// to the new window
driver.SwitchTo().Window(driver.WindowHandles.ToList().First());
//or
driver.SwitchTo().DefaultContent();