PiT 25.1: `resizeViewPortTo(x,y)` doesn't work correctly on windows

[ZheSun88]

we run the PR validation for testbench-demo project on both Linux and Windows.
in the window build log, i saw the following error for ScreenshotIT

java.lang.UnsupportedOperationException: Viewport couldn't be adjusted.
	at com.vaadin.testbench.commands.TestBenchCommandExecutor.resizeViewPortTo(TestBenchCommandExecutor.java:311)
	at com.vaadin.testbenchexample.advanced.ScreenshotIT.setUp(ScreenshotIT.java:32)
	at java.base/java.lang.reflect.Method.invoke(Method.java:580)
Caused by: java.lang.Exception: Viewport size couldn't be set to the desired '500,400' got '484,359'.
	at com.vaadin.testbench.commands.TestBenchCommandExecutor.resizeViewPortTo(TestBenchCommandExecutor.java:305)

workaround :
update the testbench call testbench():resizeViewPortTo(500,400) to

getDriver().manage().window().setSize(new Dimension(500, 400));

makes the validation green again.

you can find both of the logs from links below

✅ https://github.com/vaadin/testbench-demo/actions/runs/22945919067/job/66598161360
❌ https://github.com/vaadin/testbench-demo/actions/runs/22905440292/job/66462715839#step:8:287

[ZheSun88]

analysis from claude:

The resizeViewPortTo method tries to precisely match viewport dimensions by detecting browser chrome offsets via JavaScript, then throws UnsupportedOperationException if the viewport doesn't match exactly.
This fails in headless Chrome where the assumed offsets (106px for browser chrome) don't apply.

The fix: Use Selenium's standard window().setSize() API directly, which reliably sets the window dimensions without the strict viewport validation.

[caalador]

Just a thought, is the "screen" big enough for 500,400? as the code actually sets the size checks the diff and then re-sets the size to get it to the correct size.
At least locally none of 3 runs failed for any of the tests in testbench-demo.
There is no screenshots as build artifacts so can not check what they show for the error.