[SOLVED] Webdriverio is not working with firefox on selenium-standalone

I have wdio config as below

exports.config = {
//
// ====================
// Runner Configuration
// ====================
//
//
// ==================
// Specify Test Files
// ==================
// Define which test specs should run. The pattern is relative to the directory
// from which `wdio` was called.
//
// The specs are defined as an array of spec files (optionally using wildcards
// that will be expanded). The test for each spec file will be run in a separate
// worker process. In order to have a group of spec files run in the same worker
// process simply enclose them in an array within the specs array.
//
// If you are calling `wdio` from an NPM script (see https://docs.npmjs.com/cli/run-script),
// then the current working directory is where your `package.json` resides, so `wdio`
// will be called from there.
//
specs: [
    './test/specs/**/*.js'
],
// Patterns to exclude.
exclude: [
    // 'path/to/excluded/files'
],
//
// ============
// Capabilities
// ============
// Define your capabilities here. WebdriverIO can run multiple capabilities at the same
// time. Depending on the number of capabilities, WebdriverIO launches several test
// sessions. Within your capabilities you can overwrite the spec and exclude options in
// order to group specific specs to a specific capability.
//
// First, you can define how many instances should be started at the same time. Let's
// say you have 3 different capabilities (Chrome, Firefox, and Safari) and you have
// set maxInstances to 1; wdio will spawn 3 processes. Therefore, if you have 10 spec
// files and you set maxInstances to 10, all spec files will get tested at the same time
// and 30 processes will get spawned. The property handles how many capabilities
// from the same test should run tests.
//
maxInstances: 10,
//
// If you have trouble getting all important capabilities together, check out the
// Sauce Labs platform configurator - a great tool to configure your capabilities:
// https://saucelabs.com/platform/platform-configurator
//
capabilities: [{

    // // maxInstances can get overwritten per capability. So if you have an in-house Selenium
    // // grid with only 5 firefox instances available you can make sure that not more than
    // // 5 instances get started at a time.
    // maxInstances: 5,
    // //
    // browserName: 'chrome',
    // acceptInsecureCerts: true
    // // If outputDir is provided WebdriverIO can capture driver session logs
    // // it is possible to configure which logTypes to include/exclude.
    // // excludeDriverLogs: ['*'], // pass '*' to exclude all driver session logs
    // // excludeDriverLogs: ['bugreport', 'server'],
    //maxInstances: 1,
    browserName: 'firefox', 
    //marionette: true
}],
//
// ===================
// Test Configurations
// ===================
// Define all options that are relevant for the WebdriverIO instance here
//
// Level of logging verbosity: trace | debug | info | warn | error | silent
logLevel: 'info',
//
// Set specific log levels per logger
// loggers:
// - webdriver, webdriverio
// - @wdio/browserstack-service, @wdio/devtools-service, @wdio/sauce-service
// - @wdio/mocha-framework, @wdio/jasmine-framework
// - @wdio/local-runner
// - @wdio/sumologic-reporter
// - @wdio/cli, @wdio/config, @wdio/utils
// Level of logging verbosity: trace | debug | info | warn | error | silent
// logLevels: {
//     webdriver: 'info',
//     '@wdio/appium-service': 'info'
// },
//
// If you only want to run your tests until a specific amount of tests have failed use
// bail (default is 0 - don't bail, run all tests).
bail: 0,
//
// Set a base URL in order to shorten url command calls. If your `url` parameter starts
// with `/`, the base url gets prepended, not including the path portion of your baseUrl.
// If your `url` parameter starts without a scheme or `/` (like `some/path`), the base url
// gets prepended directly.
baseUrl: 'http://localhost',
//
// Default timeout for all waitFor* commands.
waitforTimeout: 10000,
//
// Default timeout in milliseconds for request
// if browser driver or grid doesn't send response
connectionRetryTimeout: 120000,
//
// Default request retries count
connectionRetryCount: 3,
//
// Test runner services
// Services take over a specific job you don't want to take care of. They enhance
// your test setup with almost no effort. Unlike plugins, they don't add new
// commands. Instead, they hook themselves up into the test process.
services: ['selenium-standalone'],

// Framework you want to run your specs with.
// The following are supported: Mocha, Jasmine, and Cucumber
// see also: https://webdriver.io/docs/frameworks
//
// Make sure you have the wdio adapter package for the specific framework installed
// before running any tests.
framework: 'mocha',
//
// The number of times to retry the entire specfile when it fails as a whole
// specFileRetries: 1,
//
// Delay in seconds between the spec file retry attempts
// specFileRetriesDelay: 0,
//
// Whether or not retried specfiles should be retried immediately or deferred to the end of the queue
// specFileRetriesDeferred: false,
//
// Test reporter for stdout.
// The only one supported by default is 'dot'
// see also: https://webdriver.io/docs/dot-reporter
reporters: ['spec'],



//
// Options to be passed to Mocha.
// See the full list at http://mochajs.org/
mochaOpts: {
    ui: 'bdd',
    timeout: 60000
},
//
// =====
// Hooks
// =====
// WebdriverIO provides several hooks you can use to interfere with the test process in order to enhance
// it and to build services around it. You can either apply a single function or an array of
// methods to it. If one of them returns with a promise, WebdriverIO will wait until that promise got
// resolved to continue.
/**
 * Gets executed once before all workers get launched.
 * @param {Object} config wdio configuration object
 * @param {Array.<Object>} capabilities list of capabilities details
 */
// onPrepare: function (config, capabilities) {
// },
/**
 * Gets executed before a worker process is spawned and can be used to initialise specific service
 * for that worker as well as modify runtime environments in an async fashion.
 * @param  {String} cid      capability id (e.g 0-0)
 * @param  {[type]} caps     object containing capabilities for session that will be spawn in the worker
 * @param  {[type]} specs    specs to be run in the worker process
 * @param  {[type]} args     object that will be merged with the main configuration once worker is initialized
 * @param  {[type]} execArgv list of string arguments passed to the worker process
 */
// onWorkerStart: function (cid, caps, specs, args, execArgv) {
// },
/**
 * Gets executed just after a worker process has exited.
 * @param  {String} cid      capability id (e.g 0-0)
 * @param  {Number} exitCode 0 - success, 1 - fail
 * @param  {[type]} specs    specs to be run in the worker process
 * @param  {Number} retries  number of retries used
 */
// onWorkerEnd: function (cid, exitCode, specs, retries) {
// },
/**
 * Gets executed just before initialising the webdriver session and test framework. It allows you
 * to manipulate configurations depending on the capability or spec.
 * @param {Object} config wdio configuration object
 * @param {Array.<Object>} capabilities list of capabilities details
 * @param {Array.<String>} specs List of spec file paths that are to be run
 * @param {String} cid worker id (e.g. 0-0)
 */
// beforeSession: function (config, capabilities, specs, cid) {
// },
/**
 * Gets executed before test execution begins. At this point you can access to all global
 * variables like `browser`. It is the perfect place to define custom commands.
 * @param {Array.<Object>} capabilities list of capabilities details
 * @param {Array.<String>} specs        List of spec file paths that are to be run
 * @param {Object}         browser      instance of created browser/device session
 */
// before: function (capabilities, specs) {
// },
/**
 * Runs before a WebdriverIO command gets executed.
 * @param {String} commandName hook command name
 * @param {Array} args arguments that command would receive
 */
// beforeCommand: function (commandName, args) {
// },
/**
 * Hook that gets executed before the suite starts
 * @param {Object} suite suite details
 */
// beforeSuite: function (suite) {
// },
/**
 * Function to be executed before a test (in Mocha/Jasmine) starts.
 */
// beforeTest: function (test, context) {
// },
/**
 * Hook that gets executed _before_ a hook within the suite starts (e.g. runs before calling
 * beforeEach in Mocha)
 */
// beforeHook: function (test, context) {
// },
/**
 * Hook that gets executed _after_ a hook within the suite starts (e.g. runs after calling
 * afterEach in Mocha)
 */
// afterHook: function (test, context, { error, result, duration, passed, retries }) {
// },
/**
 * Function to be executed after a test (in Mocha/Jasmine only)
 * @param {Object}  test             test object
 * @param {Object}  context          scope object the test was executed with
 * @param {Error}   result.error     error object in case the test fails, otherwise `undefined`
 * @param {Any}     result.result    return object of test function
 * @param {Number}  result.duration  duration of test
 * @param {Boolean} result.passed    true if test has passed, otherwise false
 * @param {Object}  result.retries   informations to spec related retries, e.g. `{ attempts: 0, limit: 0 }`
 */
// afterTest: function(test, context, { error, result, duration, passed, retries }) {
// },


/**
 * Hook that gets executed after the suite has ended
 * @param {Object} suite suite details
 */
// afterSuite: function (suite) {
// },
/**
 * Runs after a WebdriverIO command gets executed
 * @param {String} commandName hook command name
 * @param {Array} args arguments that command would receive
 * @param {Number} result 0 - command success, 1 - command error
 * @param {Object} error error object if any
 */
// afterCommand: function (commandName, args, result, error) {
// },
/**
 * Gets executed after all tests are done. You still have access to all global variables from
 * the test.
 * @param {Number} result 0 - test pass, 1 - test fail
 * @param {Array.<Object>} capabilities list of capabilities details
 * @param {Array.<String>} specs List of spec file paths that ran
 */
// after: function (result, capabilities, specs) {
// },
/**
 * Gets executed right after terminating the webdriver session.
 * @param {Object} config wdio configuration object
 * @param {Array.<Object>} capabilities list of capabilities details
 * @param {Array.<String>} specs List of spec file paths that ran
 */
// afterSession: function (config, capabilities, specs) {
// },
/**
 * Gets executed after all workers got shut down and the process is about to exit. An error
 * thrown in the onComplete hook will result in the test run failing.
 * @param {Object} exitCode 0 - success, 1 - fail
 * @param {Object} config wdio configuration object
 * @param {Array.<Object>} capabilities list of capabilities details
 * @param {<Object>} results object containing test results
 */
// onComplete: function(exitCode, config, capabilities, results) {
// },
/**
* Gets executed when a refresh happens.
* @param {String} oldSessionId session ID of the old session
* @param {String} newSessionId session ID of the new session
*/
// onReload: function(oldSessionId, newSessionId) {
// }

}

and my package json has

{
    "name": "webdriverio-tests",
    "version": "0.1.0",
    "private": true,
    "devDependencies": {
        "@wdio/cli": "^7.24.0",
        "@wdio/local-runner": "^7.24.0",
        "@wdio/mocha-framework": "^7.24.0",
        "@wdio/selenium-standalone-service": "^7.24.0",
        "@wdio/spec-reporter": "^7.24.0"
    },
    "scripts": {
        "wdio": "wdio run wdio.conf.js"
    }
}

and trying to run the demo test but then getting error like

C:\TestProject\wdioForSG>npm run wdio

> webdriverio-tests@0.1.0 wdio
> wdio run wdio.conf.js


Execution of 1 workers started at 2022-09-19T05:21:43.028Z

2022-09-19T05:21:43.142Z INFO @wdio/cli:launcher: Run onPrepare hook
Failed to connect to selenium. Attempts left: 115
 connect ECONNREFUSED 127.0.0.1:4444
2022-09-19T05:21:51.350Z INFO @wdio/cli:launcher: Run onWorkerStart hook
2022-09-19T05:21:51.351Z INFO @wdio/local-runner: Start worker 0-0 with arg: run,wdio.conf.js
[0-0] 2022-09-19T05:21:51.834Z INFO @wdio/local-runner: Run worker command: run
[0-0] RUNNING in firefox - C:\TestProject\wdioForSG\test\specs\example.e2e.js
[0-0] 2022-09-19T05:21:52.103Z INFO webdriver: Initiate new session using the WebDriver protocol
[0-0] 2022-09-19T05:21:52.108Z INFO webdriver: [POST] http://localhost:4444/wd/hub/session
[0-0] 2022-09-19T05:21:52.108Z INFO webdriver: DATA {
[0-0]   capabilities: { alwaysMatch: { browserName: 'firefox' }, firstMatch: [ {} ] },
[0-0]   desiredCapabilities: { browserName: 'firefox' }
[0-0] }
[0-0] 2022-09-19T05:21:52.653Z WARN webdriver: Request failed with status 500 due to Could not start a new session. Error while creating session with the driver service. Stopping driver service: Could not start a new session. Response code 500. Message: Expected browser binary location, but unable to find binary in default location, no 'moz:firefoxOptions.binary' capability provided, and no binary flag set on the command line
[0-0] Build info: version: '4.0.0', revision: '3a21814679'
[0-0] System info: host: 'B36PZ53', ip: '10.51.20.50', os.name: 'Windows 11', os.arch: 'amd64', os.version: '10.0', java.version: '11.0.16'
[0-0] Driver info: driver.version: unknown
[0-0] Build info: version: '4.0.0', revision: '3a21814679'
[0-0] System info: host: 'B36PZ53', ip: '10.51.20.50', os.name: 'Windows 11', os.arch: 'amd64', os.version: '10.0', java.version: '11.0.16'
[0-0] Driver info: driver.version: unknown
[0-0] 2022-09-19T05:21:52.653Z INFO webdriver: Retrying 1/3
[0-0] 2022-09-19T05:21:52.653Z INFO webdriver: [POST] http://localhost:4444/wd/hub/session
[0-0] 2022-09-19T05:21:52.653Z INFO webdriver: DATA {
[0-0]   capabilities: { alwaysMatch: { browserName: 'firefox' }, firstMatch: [ {} ] },
[0-0]   desiredCapabilities: { browserName: 'firefox' }
[0-0] }
[0-0] 2022-09-19T05:21:57.453Z WARN webdriver: Request failed with status 500 due to Could not start a new session. Error while creating session with the driver service. Stopping driver service: Could not start a new session. Response code 500. Message: Expected browser binary location, but unable to find binary in default location, no 'moz:firefoxOptions.binary' capability provided, and no binary flag set on the command line
[0-0] Build info: version: '4.0.0', revision: '3a21814679'
[0-0] System info: host: 'B36PZ53', ip: '10.51.20.50', os.name: 'Windows 11', os.arch: 'amd64', os.version: '10.0', java.version: '11.0.16'
[0-0] Driver info: driver.version: unknown
[0-0] Build info: version: '4.0.0', revision: '3a21814679'
[0-0] System info: host: 'B36PZ53', ip: '10.51.20.50', os.name: 'Windows 11', os.arch: 'amd64', os.version: '10.0', java.version: '11.0.16'
[0-0] Driver info: driver.version: unknown
[0-0] 2022-09-19T05:21:57.454Z INFO webdriver: Retrying 2/3
[0-0] 2022-09-19T05:21:57.454Z INFO webdriver: [POST] http://localhost:4444/wd/hub/session
[0-0] 2022-09-19T05:21:57.454Z INFO webdriver: DATA {
[0-0]   capabilities: { alwaysMatch: { browserName: 'firefox' }, firstMatch: [ {} ] },
[0-0]   desiredCapabilities: { browserName: 'firefox' }
[0-0] }
[0-0] 2022-09-19T05:22:02.450Z WARN webdriver: Request failed with status 500 due to Could not start a new session. Error while creating session with the driver service. Stopping driver service: Could not start a new session. Response code 500. Message: Expected browser binary location, but unable to find binary in default location, no 'moz:firefoxOptions.binary' capability provided, and no binary flag set on the command line
[0-0] Build info: version: '4.0.0', revision: '3a21814679'
[0-0] System info: host: 'B36PZ53', ip: '10.51.20.50', os.name: 'Windows 11', os.arch: 'amd64', os.version: '10.0', java.version: '11.0.16'
[0-0] Driver info: driver.version: unknown
[0-0] Build info: version: '4.0.0', revision: '3a21814679'
[0-0] System info: host: 'B36PZ53', ip: '10.51.20.50', os.name: 'Windows 11', os.arch: 'amd64', os.version: '10.0', java.version: '11.0.16'
[0-0] Driver info: driver.version: unknown
[0-0] 2022-09-19T05:22:02.451Z INFO webdriver: Retrying 3/3
[0-0] 2022-09-19T05:22:02.451Z INFO webdriver: [POST] http://localhost:4444/wd/hub/session
[0-0] 2022-09-19T05:22:02.451Z INFO webdriver: DATA {
[0-0]   capabilities: { alwaysMatch: { browserName: 'firefox' }, firstMatch: [ {} ] },
[0-0]   desiredCapabilities: { browserName: 'firefox' }
[0-0] }
[0-0] 2022-09-19T05:22:07.461Z ERROR webdriver: Request failed with status 500 due to WebDriver Error: Could not start a new session. Error while creating session with the driver service. Stopping driver service: Could not start a new session. Response code 500. Message: Expected browser binary location, but unable to find binary in default location, no 'moz:firefoxOptions.binary' capability provided, and no binary flag set on the command line
[0-0] Build info: version: '4.0.0', revision: '3a21814679'
[0-0] System info: host: 'B36PZ53', ip: '10.51.20.50', os.name: 'Windows 11', os.arch: 'amd64', os.version: '10.0', java.version: '11.0.16'
[0-0] Driver info: driver.version: unknown
[0-0] Build info: version: '4.0.0', revision: '3a21814679'
[0-0] System info: host: 'B36PZ53', ip: '10.51.20.50', os.name: 'Windows 11', os.arch: 'amd64', os.version: '10.0', java.version: '11.0.16'
[0-0] Driver info: driver.version: unknown
[0-0] 2022-09-19T05:22:07.462Z ERROR webdriver: WebDriver Error: Could not start a new session. Error while creating session with the driver service. Stopping driver service: Could not start a new session. Response code 500. Message: Expected browser binary location, but unable to find binary in default location, no 'moz:firefoxOptions.binary' capability provided, and no binary flag set on the command line
[0-0] Build info: version: '4.0.0', revision: '3a21814679'
[0-0] System info: host: 'B36PZ53', ip: '10.51.20.50', os.name: 'Windows 11', os.arch: 'amd64', os.version: '10.0', java.version: '11.0.16'
[0-0] Driver info: driver.version: unknown
[0-0] Build info: version: '4.0.0', revision: '3a21814679'
[0-0] System info: host: 'B36PZ53', ip: '10.51.20.50', os.name: 'Windows 11', os.arch: 'amd64', os.version: '10.0', java.version: '11.0.16'
[0-0] Driver info: driver.version: unknown
[0-0]     at getErrorFromResponseBody (C:\TestProject\wdioForSG\node_modules\webdriver\build\utils.js:198:12)
[0-0]     at NodeJSRequest._request (C:\TestProject\wdioForSG\node_modules\webdriver\build\request\index.js:166:60)
[0-0]     at processTicksAndRejections (node:internal/process/task_queues:96:5)
[0-0]     at async startWebDriverSession (C:\TestProject\wdioForSG\node_modules\webdriver\build\utils.js:68:20)
[0-0]     at async Function.newSession (C:\TestProject\wdioForSG\node_modules\webdriver\build\index.js:46:45)
[0-0]     at async remote (C:\TestProject\wdioForSG\node_modules\webdriverio\build\index.js:77:22)
[0-0]     at async Runner._startSession (C:\TestProject\wdioForSG\node_modules\@wdio\runner\build\index.js:223:56)
[0-0]     at async Runner._initSession (C:\TestProject\wdioForSG\node_modules\@wdio\runner\build\index.js:176:25)
[0-0]     at async Runner.run (C:\TestProject\wdioForSG\node_modules\@wdio\runner\build\index.js:88:19)
[0-0] 2022-09-19T05:22:07.462Z ERROR @wdio/runner: Error: Failed to create session.
[0-0] Could not start a new session. Error while creating session with the driver service. Stopping driver service: Could not start a new session. Response code 500. Message: Expected browser binary location, but unable to find binary in default location, no 'moz:firefoxOptions.binary' capability provided, and no binary flag set on the command line
[0-0] Build info: version: '4.0.0', revision: '3a21814679'
[0-0] System info: host: 'B36PZ53', ip: '10.51.20.50', os.name: 'Windows 11', os.arch: 'amd64', os.version: '10.0', java.version: '11.0.16'
[0-0] Driver info: driver.version: unknown
[0-0] Build info: version: '4.0.0', revision: '3a21814679'
[0-0] System info: host: 'B36PZ53', ip: '10.51.20.50', os.name: 'Windows 11', os.arch: 'amd64', os.version: '10.0', java.version: '11.0.16'
[0-0] Driver info: driver.version: unknown
[0-0]     at startWebDriverSession (C:\TestProject\wdioForSG\node_modules\webdriver\build\utils.js:73:15)
[0-0]     at processTicksAndRejections (node:internal/process/task_queues:96:5)
[0-0]     at async Function.newSession (C:\TestProject\wdioForSG\node_modules\webdriver\build\index.js:46:45)
[0-0]     at async remote (C:\TestProject\wdioForSG\node_modules\webdriverio\build\index.js:77:22)
[0-0]     at async Runner._startSession (C:\TestProject\wdioForSG\node_modules\@wdio\runner\build\index.js:223:56)
[0-0]     at async Runner._initSession (C:\TestProject\wdioForSG\node_modules\@wdio\runner\build\index.js:176:25)
[0-0]     at async Runner.run (C:\TestProject\wdioForSG\node_modules\@wdio\runner\build\index.js:88:19)
[0-0] FAILED in firefox - C:\TestProject\wdioForSG\test\specs\example.e2e.js
2022-09-19T05:22:07.575Z INFO @wdio/cli:launcher: Run onWorkerEnd hook
2022-09-19T05:22:07.576Z INFO @wdio/cli:launcher: Run onComplete hook
2022-09-19T05:22:07.586Z INFO @wdio/selenium-standalone-service: shutting down all browsers

Spec Files:      0 passed, 1 failed, 1 total (100% completed) in 00:00:24

2022-09-19T05:22:07.587Z INFO @wdio/local-runner: Shutting down spawned worker
2022-09-19T05:22:07.844Z INFO @wdio/local-runner: Waiting for 0 to shut down gracefully
2022-09-19T05:22:07.846Z INFO @wdio/local-runner: shutting down

C:\TestProject\wdioForSG>

This failure only happens when I set the browser to firefox, If I set it to chrome then it works perfectly fine.

To just validate, I tried to run test on firefox v104.0.2 (64-bit) with geckodriver-v0.31.0-win64 by configuring 'npm install wdio-geckodriver-service --save-dev' and running geckodriver manually and it seems happy but as soon as I configure as selenium-standalone then it shows above error.