Auto download PDF in Firefox

You can disable plugin while setting preference. This works for me

profile = webdriver.FirefoxProfile()

profile.set_preference("browser.download.folderList",2)
profile.set_preference("browser.helperApps.alwaysAsk.force", False)
profile.set_preference("browser.download.manager.showWhenStarting",False)
profile.set_preference("browser.download.dir", os.getcwd())

//below line was missing in yours

profile.set_preference("plugin.disable_full_page_plugin_for_types", "application/pdf")
profile.set_preference("pdfjs.disabled", True)
profile.set_preference("browser.helperApps.neverAsk.saveToDisk", "application/pdf")  
driver = webdriver.Firefox(firefox_profile=profile)

Hope this helps.


For Firefox Quantum 57.0 64-bit, Selenium 3.8.1, the following solution works.

FirefoxProfile ffprofile = new FirefoxProfile();        

// Required if you want to download other than the default location
ffprofile.setPreference("browser.download.folderList", 2);
// Specify your own location
ffprofile.setPreference("browser.download.dir", "C:\\TestAutomationDataSheets\\Files_To_Download\\");
ffprofile.setPreference("browser.helperApps.neverAsk.saveToDisk", "application/pdf");
ffprofile.setPreference("pdfjs.enabledCache.state", false);

DesiredCapabilities ffcapabilities = DesiredCapabilities.firefox();
ffcapabilities.setCapability(FirefoxDriver.PROFILE, ffprofile);

WebDriver driver = new FirefoxDriver(ffcapabilities);

It doesn't make sense to me that your screenshot shows Firefox will preview pdf files, but your Firefox still pops up "Save as" dialog.

Anyway, in order to make Firefox saving pdf files to a pre-defined folder as the default behaviour, you might want to try the following code, where setting pdfjs.disabled to true will prevent Firefox previewing the files.

Also, please ensure you don't have any third party Firefox PDF viewing plugins installed. If you have Adobe Reader installed on your computer, then it sets Acrobat as the PDF viewer inside Firefox. Similarly, I used to have Sumatra PDF Firefox plugin on my computer, it overrides Firefox settings to preview PDFs no matter what's in about:config.

FirefoxProfile firefoxProfile = new FirefoxProfile();

firefoxProfile.setPreference("browser.download.folderList", 2);
firefoxProfile.setPreference("browser.download.manager.showWhenStarting", false);
firefoxProfile.setPreference("browser.download.dir", "c:\\tmp");
firefoxProfile.setPreference("browser.helperApps.neverAsk.saveToDisk", "application/pdf");

firefoxProfile.setPreference("pdfjs.disabled", true);

// Use this to disable Acrobat plugin for previewing PDFs in Firefox (if you have Adobe reader installed on your computer)
firefoxProfile.setPreference("plugin.scan.Acrobat", "99.0");
firefoxProfile.setPreference("plugin.scan.plid.all", false);

WebDriver driver = new FirefoxDriver(firefoxProfile);

// Its just a sample URL 
driver.get("http://www.energy.umich.edu/sites/default/files/pdf-sample.pdf");

Further reading:

  • Similar question I answered before: Custom browser preferences for file download for PDF file
  • Article about Plugin Scanning in Firefox: Plugin scanning
  • Download PDF files automatically in Firefox using Selenium WebDriver

This works for me:

    WebDriver driver;

    FirefoxProfile fxProfile = new FirefoxProfile();
    fxProfile.setPreference("browser.download.folderList", 2);
    fxProfile.setPreference("browser.download.manager.showWhenStarting", false);
    fxProfile.setPreference("browser.download.dir",System.getProperty("java.io.tmpdir"));
    fxProfile.setPreference("browser.helperApps.neverAsk.saveToDisk", "application/octet-stream");

    //You miss this line
    fxProfile.setPreference("browser.helperApps.alwaysAsk.force", false);

    driver = new FirefoxDriver(firefoxProfile);

Give a try.

Hope helps!