Have you read the Contributing Guidelines on issues?

• I have read the Contributing Guidelines on issues.

WebdriverIO Version

latest

Node.js Version

22.12.0

Mode

Standalone Mode

Which capabilities are you using?

No response

What happened?

After the changes #14025, command closeWindow() leads to the error(when only one window has been opened):

[chrome 131.0.6778.205 windows #0-0] Error: Malformed type for "handle" parameter of command switchToWindow
[chrome 131.0.6778.205 windows #0-0] Error: Malformed type for "handle" parameter of command switchToWindow
[chrome 131.0.6778.205 windows #0-0] Expected: string
[chrome 131.0.6778.205 windows #0-0] Actual: undefined
[chrome 131.0.6778.205 windows #0-0]
[chrome 131.0.6778.205 windows #0-0] For more info see https://w3c.github.io/webdriver/#dfn-switch-to-window

It happens for both: Bidi and classic protocols ("wdio:enforceWebDriverClassic": true)

What is your expected behavior?

According to the documentation:
The Close Window command closes the current top-level browsing context. Once done, if there are no more top-level browsing contexts open, the WebDriver session itself is closed.

So the expected result is to close the window even if it was only one window, without the error (as before the fix)

How to reproduce the bug.

await browser.url(url)
await browser.closeWindow()

Relevant log output

[chrome 131.0.6778.205 windows #0-0] Error: Malformed type for "handle" parameter of command switchToWindow
[chrome 131.0.6778.205 windows #0-0] Error: Malformed type for "handle" parameter of command switchToWindow
[chrome 131.0.6778.205 windows #0-0] Expected: string
[chrome 131.0.6778.205 windows #0-0] Actual: undefined
[chrome 131.0.6778.205 windows #0-0]
[chrome 131.0.6778.205 windows #0-0] For more info see https://w3c.github.io/webdriver/#dfn-switch-to-window
[chrome 131.0.6778.205 windows #0-0]
[chrome 131.0.6778.205 windows #0-0]     at Browser.protocolCommand (file:///C:/123123/node_modules/webdriver/build/node.js:86:15)
[chrome 131.0.6778.205 windows #0-0]     at Browser.wrapCommandFn (C:\123123\node_modules\@wdio\utils\build\index.js:893:32)
[chrome 131.0.6778.205 windows #0-0]     at process.processTicksAndRejections (node:internal/process/task_queues:105:5)
[chrome 131.0.6778.205 windows #0-0]

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Is there an existing issue for this?

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