Dismiss browser alert window when script is running in headed mode

I have a script where opening URL redirects to login screen. However, before login screen, it displays blank page with alert window (like on screenshot).
K6GUI-cant-close-alert-window

If I run script in headless mode “K6_BROWSER_HEADLESS=true” this alert window gets dismissed and script runs successfully.
However, if I try “K6_BROWSER_HEADLESS=false”, script fails.
I tried to dismiss it using keyboard “Escape” button but that doesn’t work either.

Is there any way to close alert window when it is running in “K6_BROWSER_HEADLESS=false” mode?

export default async function () {
  
  const page = browser.newPage();

  try {    
    page.goto('https://www.XXXXXX.com/YYYYYY');
    sleep(3);

//    keyboard.press('Escape');  // ERRO[0006] Uncaught (in promise) ReferenceError: keyboard is not defined
      page.keyboard.press('Escape'); // ERRO[0038] Uncaught (in promise) GoError: typing "AAAAA" in "input[name=\"usr\"]": timed out after 30s
      sleep(3);

      page.locator('input[name="usr"]').type('AAAAA');
      page.locator('input[name="pass"]').type('BBBBB');

      const submitButton = page.locator('//*[@id="SignInButton"]');
      await Promise.all([page.waitForNavigation(), submitButton.click()]);
      sleep(3);

      page.screenshot({ path: 'screenshots/screenshot.png' });

   } finally {
     page.close();
   }
}