Web Applications generate 3 different types of pop-ups; namely,
1| JavaScript PopUps
2| Browser PopUps
3| Native OS PopUps [e.g., Windows Popup like Upload/Download]
In General, the JavaScript pop-ups are generated by the web application code. Selenium provides an API to handle these JavaScript pop-ups, such as Alert
.
Eventually, the simplest way to ignore Browser pop-up and download files is done by making use of Browser profiles; There are couple of ways to do this:
- Manually involve changes on browser properties (or)
- Customize browser properties using profile setPreference
Method1
Before you start working with pop-ups on Browser profiles, make sure that the Download options are set default to Save File.
(Open Firefox) Tools > Options > Applications

Method2
Make use of the below snippet and do edits whenever necessary.
FirefoxProfile profile = new FirefoxProfile();
String path = "C:\\Test\\";
profile.setPreference("browser.download.folderList", 2);
profile.setPreference("browser.download.dir", path);
profile.setPreference("browser.download.manager.alertOnEXEOpen", false);
profile.setPreference("browser.helperApps.neverAsk.saveToDisk", "application/msword, application/csv, application/ris, text/csv, image/png, application/pdf, text/html, text/plain, application/zip, application/x-zip, application/x-zip-compressed, application/download, application/octet-stream");
profile.setPreference("browser.download.manager.showWhenStarting", false);
profile.setPreference("browser.download.manager.focusWhenStarting", false);
profile.setPreference("browser.download.useDownloadDir", true);
profile.setPreference("browser.helperApps.alwaysAsk.force", false);
profile.setPreference("browser.download.manager.alertOnEXEOpen", false);
profile.setPreference("browser.download.manager.closeWhenDone", true);
profile.setPreference("browser.download.manager.showAlertOnComplete", false);
profile.setPreference("browser.download.manager.useWindow", false);
profile.setPreference("services.sync.prefs.sync.browser.download.manager.showWhenStarting", false);
profile.setPreference("pdfjs.disabled", true);
driver = new FirefoxDriver(profile);