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• I have read the Contributing Guidelines on issues.

WebdriverIO Version

9.21.0

Node.js Version

24.7

Mode

WDIO Testrunner

Which capabilities are you using?

What happened?

I am getting below provided error after i have upgraded my webdriver io version from V8 to V9 (9.21.0). While requesting browser from selenium grid (4.38.0) i am getting below provided error, I tried tweaking the capabilities in multiple ways but its still not resolved. So could you please check this.

Error:- webDriverError: overlapping keys between w3c always and first match capabilities: [requester:project-id, requester:project-branch-id] when running "https://selenium-hub:4444/selenium/session" with method post and args

But at the same time test is still working in same selenium grid with V8 version of webdriver io

What is your expected behavior?

No response

How to reproduce the bug.

created a webdriver io test automation framework with latest version 9.21.0 and tried to run test in selenium grid.

Relevant log output

Error:-  @wdio/runner webDriverError: overlapping keys between w3c always and first match capabilities: [requester:project-id, requester:project-branch-id]  when running "https://selenium-hub:4444/selenium/session" with method post and args {capabilities}

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Is there an existing issue for this?

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