emulateMedia([options])

This method changes the CSS @media type through the media argument, and/or the 'prefers-colors-scheme' media feature, using the colorScheme argument.

Parameter	Type	Default	Description
options	object	`null`
options.colorScheme	string	`''`	Emulates `'prefers-colors-scheme'` media feature, supported values are `'light'`, `'dark'`, and `'no-preference'`.
options.media	string	`''`	Changes the CSS media type of the page. The only allowed values are `'screen'`, and `'print'`.
options.reducedMotion	string	`''`	Emulates `'prefers-reduced-motion'` media feature, supported values are `'reduce'`, `'no-preference'`.

Returns

Type	Description
`Promise<void>`	A Promise that fulfills when the media is emulated.

Example

import { browser } from 'k6/browser';

export const options = {
  scenarios: {
    browser: {
      executor: 'shared-iterations',
      options: {
        browser: {
          type: 'chromium',
        },
      },
    },
  },
};

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

  await page.goto('https://test.k6.io/browser.php');
  console.log(await page.evaluate(() => matchMedia('screen').matches)); // true
}