ChromiumOS Testing on Sauce Labs

Beta

Sauce Labs supports automated web testing on ChromiumOS virtual machines. ChromiumOS is the open-source platform behind Google's ChromeOS — it shares the same Chromium browser engine, rendering pipeline, and web platform APIs. You can validate your web applications against the same browser behavior that real ChromeOS users experience, directly from the Sauce Labs cloud.

What You'll Need

• A Sauce Labs account (Log in or sign up for a free trial)
• Your Sauce Labs SAUCE_USERNAME and SAUCE_ACCESS_KEY (find them in User Settings)
• A Selenium or WebDriver test framework configured to run against a remote endpoint
• (Optional) Sauce Connect 5 installed and a tunnel started, if you need to test applications behind a firewall or on a staging environment

How ChromiumOS Relates to ChromeOS

ChromiumOS is the open-source foundation of Google's ChromeOS. The two share the same browser engine and web platform behavior. ChromeOS adds Google-proprietary features like the Play Store and Google Assistant — none of which affect web application testing. For web testing purposes, ChromiumOS provides functionally equivalent coverage to ChromeOS.

How to Run Tests on ChromiumOS

Live Testing

You can run interactive manual testing sessions on ChromiumOS virtual machines through the Sauce Labs Live Testing interface.

1. Navigate to Live Testing > Cross Browser in Sauce Labs.
2. Select Chrome 144 or 146 from the browser version dropdown. These are the only two versions supported during the beta.
3. In the OS Version selector, choose ChromiumOS.
4. Click Start Test Session to launch the virtual machine.

Scrolling in Live Testing

ChromiumOS live testing sessions use touch-based scrolling. To scroll the page, click and drag inside the browser viewport — standard mouse wheel or trackpad scrolling is not supported.

Automated Tests

Set the following capabilities in your test configuration to target a ChromiumOS virtual machine on Sauce Labs.

Capability	Value
platformName	ChromiumOS
browserName	googlechrome
browserVersion	144

Java

ChromiumOS Test Configuration

ChromeOptions options = new ChromeOptions();
options.setPlatformName("ChromiumOS");
options.setBrowserVersion("144");

Map<String, Object> sauceOptions = new HashMap<>();
sauceOptions.put("username", System.getenv("SAUCE_USERNAME"));
sauceOptions.put("accessKey", System.getenv("SAUCE_ACCESS_KEY"));
sauceOptions.put("name", "<your test name>");
options.setCapability("sauce:options", sauceOptions);

WebDriver driver = new RemoteWebDriver(
    new URL("https://ondemand.us-west-1.saucelabs.com:443/wd/hub"),
    options
);

Node.js

ChromiumOS Test Configuration

const capabilities = {
  platformName: 'ChromiumOS',
  browserName: 'googlechrome',
  browserVersion: '144',
  'sauce:options': {
    username: process.env.SAUCE_USERNAME,
    accessKey: process.env.SAUCE_ACCESS_KEY,
    name: '<your test name>'
  }
};

const driver = await new Builder()
  .usingServer('https://ondemand.us-west-1.saucelabs.com:443/wd/hub')
  .withCapabilities(capabilities)
  .build();

Python

ChromiumOS Test Configuration

from selenium.webdriver.chrome.options import Options as ChromeOptions

options = ChromeOptions()
options.platform_name = "ChromiumOS"
options.browser_version = "144"

sauce_options = {
    "username": os.environ["SAUCE_USERNAME"],
    "accessKey": os.environ["SAUCE_ACCESS_KEY"],
    "name": "<your test name>"
}
options.set_capability("sauce:options", sauce_options)

driver = webdriver.Remote(
    command_executor="https://ondemand.us-west-1.saucelabs.com:443/wd/hub",
    options=options
)

Ruby

ChromiumOS Test Configuration

options = Selenium::WebDriver::Options.chrome(
  platform_name: 'ChromiumOS',
  browser_version: '144',
  'sauce:options': {
    username: ENV['SAUCE_USERNAME'],
    access_key: ENV['SAUCE_ACCESS_KEY'],
    name: '<your test name>'
  }
)

driver = Selenium::WebDriver.for(
  :remote,
  url: 'https://ondemand.us-west-1.saucelabs.com:443/wd/hub',
  options: options
)

C#

ChromiumOS Test Configuration

var options = new ChromeOptions();
options.PlatformName = "ChromiumOS";
options.BrowserVersion = "144";
options.AddAdditionalOption("sauce:options", new Dictionary<string, object>
{
    { "username", Environment.GetEnvironmentVariable("SAUCE_USERNAME") },
    { "accessKey", Environment.GetEnvironmentVariable("SAUCE_ACCESS_KEY") },
    { "name", "<your test name>" }
});

var driver = new RemoteWebDriver(
    new Uri("https://ondemand.us-west-1.saucelabs.com:443/wd/hub"),
    options
);

No additional flags or special capabilities are required to launch a session — set the platform to ChromiumOS and use the standard Chrome browser and Sauce options.

Configuring Screen Resolution

ChromiumOS virtual machines support multiple screen resolutions. If you don't set a screenResolution capability, sessions launch at the default resolution of 1920x1080.

To request a specific resolution, set screenResolution inside sauce:options:

Resolution	Aspect Ratio	Notes
1280x720	16:9	HD — smallest supported size
1366x768	16:9	common Chromebook native resolution
1536x864	16:9
1600x900	16:9
1920x1080	16:9	Full HD
2880x1620	16:9	QHD+ — largest supported size

Java

Setting screenResolution

sauceOptions.put("screenResolution", "1920x1080");
options.setCapability("sauce:options", sauceOptions);

Node.js

Setting screenResolution

'sauce:options': {
  // ...other sauce:options,
  screenResolution: '1920x1080'
}

Python

Setting screenResolution

sauce_options["screenResolution"] = "1920x1080"
options.set_capability("sauce:options", sauce_options)

Ruby

Setting screenResolution

'sauce:options': {
  # ...other sauce:options,
  screenResolution: '1920x1080'
}

C#

Setting screenResolution

sauceOptions.Add("screenResolution", "1920x1080");

Unsupported Resolutions

Requesting a screenResolution value outside the supported list will cause your session to fail to start. Always pick a value from the table above.

Using Sauce Connect Tunnels

ChromiumOS testing supports Sauce Connect 5 tunnels for reaching applications behind a corporate firewall or hosted on a staging environment. Start a tunnel using the Sauce Connect 5 client, then route your test traffic through it by setting the tunnelName capability under sauce:options. If you're using a tunnel owned by another user in your organization, also set tunnelOwner.

Capability	Type	Description
tunnelName	string	The name of the running Sauce Connect 5 tunnel.
tunnelOwner	string	The Sauce Labs username of the tunnel owner. Required only when the tunnel is owned by another user.

Java

Routing Through a Tunnel

sauceOptions.put("tunnelName", "<your-tunnel-name>");
// Required only for shared tunnels owned by another user:
sauceOptions.put("tunnelOwner", "<tunnel-owner-username>");
options.setCapability("sauce:options", sauceOptions);

Node.js

Routing Through a Tunnel

'sauce:options': {
  // ...other sauce:options,
  tunnelName: '<your-tunnel-name>',
  // tunnelOwner only needed for shared tunnels:
  tunnelOwner: '<tunnel-owner-username>'
}

Python

Routing Through a Tunnel

sauce_options["tunnelName"] = "<your-tunnel-name>"
# Required only for shared tunnels owned by another user:
sauce_options["tunnelOwner"] = "<tunnel-owner-username>"
options.set_capability("sauce:options", sauce_options)

Ruby

Routing Through a Tunnel

'sauce:options': {
  # ...other sauce:options,
  tunnelName: '<your-tunnel-name>',
  # tunnelOwner only needed for shared tunnels:
  tunnelOwner: '<tunnel-owner-username>'
}

C#

Routing Through a Tunnel

sauceOptions.Add("tunnelName", "<your-tunnel-name>");
// Required only for shared tunnels owned by another user:
sauceOptions.Add("tunnelOwner", "<tunnel-owner-username>");

Sauce Connect Version

ChromiumOS supports Sauce Connect 5 only. Earlier Sauce Connect versions are not compatible with ChromiumOS sessions. If you're upgrading, see the Sauce Connect 5 migration guide.

Limitations

This feature is in Beta. The following constraints apply during the beta period:

• Limited Chrome versions — Only Chrome 144 and 146 is supported. Additional versions will be added through general availability, including monthly releases alongside Chrome browser updates.

Known Issues

Area	Description	Status
Screen Recordings	Screen recordings for ChromiumOS tests may occasionally display flickering or visual artifacts during playback.	Investigating