Support for Firefox WebExtensions

[zalmoxisus]

Mozilla introduced new WebExtensions API, which works already in Firefox Nightly. The old CPOWs extensions will be deprecated.

Trying to load an extension to Firefox Nightly, Seenium tries to find install.rdf, which doesn't exist anymore.

    var firefox = require('selenium-webdriver/firefox');
    var binary = new firefox.Binary('/Applications/FirefoxNightly.app/Contents/MacOS/firefox');
    var profile = new firefox.Profile();
    profile.addExtension('./build/firefox');
    var options = new firefox.Options()
      .setProfile(profile)
      .setBinary(binary);
    this.driver = new firefox.Driver(options);

Any plans to support the new extension format for firefox?

[jleyba]

We haven't been able been able to get the webdriver.xpi extension (i.e. the FirefoxDriver) signed by Mozilla, and I don't believe we will. This particular feature may have to way for Marionette (Mozilla's WebDriver implementation).

[cmolocznik]

Below is a workaround I use written in Java. You just need to copy the entire .xpi to the "[PATH_TO_FIREFOX_PROFILE]/extensions" directory. Firefox will unpack and install automatically when launched via FirefoxDriver.

import org.openqa.selenium.firefox.internal.Extension;

import java.io.File;
import java.io.IOException;
import java.nio.file.Files;
import java.nio.file.Paths;
import java.nio.file.StandardCopyOption;

public class FirefoxWebExtension implements Extension {
    private final File toInstall;

    public FirefoxWebExtension(File toInstall) {
        this.toInstall = toInstall;
    }

    @Override
    public void writeTo(File extensionsDir) throws IOException {
        if (!extensionsDir.exists()) {
            extensionsDir.mkdirs();
        }
        Files.copy(
                toInstall.toPath(),
                Paths.get(
                        extensionsDir.getAbsolutePath(),
                        toInstall.getName()
                ),
                StandardCopyOption.REPLACE_EXISTING
        );
    }
}

[alexristich]

@cmolocznik I'm new to Selenium, so I'm not too familiar with the project structure. Where would your workaround be placed in order to be functional?

[tobli]

See #3846

[jleyba]

Fixed by 2f1df98