[🐛 Bug]: BROWSERSTACK_MISSING_CAPS when trying to have both Browserstack and "Chrome standalone"

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• I have read the Contributing Guidelines on issues.

WebdriverIO Version

latest

Node.js Version

latest

Mode

WDIO Testrunner

Which capabilities are you using?

{
        browserName: 'chrome',
        maxInstances: 1,
        'goog:chromeOptions': {
            args: ['--headless', '--disable-gpu', '--no-sandbox', '--disable-dev-shm-usage']
        }
    }

What happened?

I want to run both against Browserstack App Live (a mobile app) AND perform API calls outside of said app. In order to do that I have browserstack service, and I'm creating a standalone browser against it. Then, in my conf file, I only have a headless chrome. This has worked for me in other runners using multiple browsers, and using appium + chrome, but fails with browserstack.

I tried several ways of removing all bstack:options capabilities so that Browserstack service doesn't pick chrome as a browser it should instantiate but couldn't make it work.

Also, the documentation mentions a use case like mine here https://webdriver.io/docs/multiremote/#using-wdio-testrunner , but it is outdated since it suggests using the selenium-standalone service (and I tried anyway).

Similar conf but with appium works like this:

    // Headless Chrome capabilities
    capabilities: [{
        browserName: 'chrome',
        maxInstances: 1,
        'goog:chromeOptions': {
            args: ['--headless', '--disable-gpu', '--no-sandbox', '--disable-dev-shm-usage']
        }
    }],

    services: [
        ['appium', {
            args: {
                address: 'localhost',
                port: 4723,
            },
            logPath: './logs'
        }],
        ['shared-store'],
    ],

For both cases, I instantiate the secondary browser with:

browser = await remote({
            hostname: hostname,
            port: port,
            path: path,
            capabilities
        })

What is your expected behavior?

If the capabilities don't have bstack:options, instantiate a standalone chrome (NOT using Browserstack).

How to reproduce the bug.

Conf file extract:

    // Headless Chrome capabilities
    capabilities: [{
        browserName: 'chrome',
        maxInstances: 1,
        'goog:chromeOptions': {
            args: ['--headless', '--disable-gpu', '--no-sandbox', '--disable-dev-shm-usage']
        }
    }],

    user: process.env.BROWSERSTACK_USERNAME,
    key: process.env.BROWSERSTACK_ACCESS_KEY,
    services: [
        ['browserstack', {
            app: process.env.IOS_APP_ID,
            buildIdentifier: "${BUILD_NUMBER}",
            browserstackLocal: true,
            testObservability: true,
            percy: false,
            percyCaptureMode: 'auto'
        }],
        ['shared-store'],
    ],

Relevant log output

[0-0] 2025-04-23T17:19:07.240Z WARN webdriver: WebDriverError: [BROWSERSTACK_MISSING_CAPS] The ["platformName"] capabilities are missing in your test script. Please refer to our capability builder - https://www.browserstack.com/app-automate/capabilities?tag=w3c when running "https://hub-cloud.browserstack.com/wd/hub/session" with method "POST" and args "{"capabilities":{"alwaysMatch":{"browserName":"chrome","goog:chromeOptions":{"args":["--headless","--disable-gpu","--no-sandbox","--disable-dev-shm-usage"]},"bstack:options":{"wdioService":"9.7.1","testhubBuildUuid":"SOMETHING","buildProductMap":{"observability":true,"accessibility":false,"percy":false,"automate":false,"app_automate":true},"local":true},"wdio:sharedStoreServicePort":46735,"appium:app":"bs://SOMETHING","webSocketUrl":true,"unhandledPromptBehavior":"ignore"},"firstMatch":[{}]}}"

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Is there an existing issue for this?

• I have searched the existing issues