It's not possible to find an element outside of the web page using Selenium.
To simulate the mouse leaving the web page, you can use JavaScript to trigger a mouseleave event on the body element of the web page. Here's some sample code to do that:
var event = new MouseEvent('mouseleave', {
view: window,
bubbles: true,
cancelable: true
});
This code creates a new MouseEvent object with the mouseleave event type, and dispatches it on the document.body element. This simulates the mouse leaving the web page and should trigger the desired popup to appear.
Note that you can execute this code using the executeScript method of the JavascriptExecutor interface in Selenium, like this:
Thread.sleep(5000);
JavascriptExecutor js = (JavascriptExecutor) driver;
js.executeScript("var event = new MouseEvent('mouseleave', {view: window, bubbles: true, cancelable: true}); document.body.dispatchEvent(event);");
I hope this helps! Let me know if you have any further questions.