How to set the browser's language in Cypress.io (electron/chrome)?

from Gleb Bahmutov:

you set it during cy.visit using onBeforeLoad with something like Object.defineProperty(navigator, 'language', { value: 'de-GE' })

src: https://gitter.im/cypress-io/cypress?at=5d61408a07d1ff39f8769545

To set the language in the browser and also for request, which was what I had to do for my tests, the following worked for me:

cy.visit('url', {
    onBeforeLoad(win) {
      Object.defineProperty(win.navigator, 'language', { value: 'de-DE' });
      Object.defineProperty(win.navigator, 'languages', { value: ['de'] });
      Object.defineProperty(win.navigator, 'accept_languages', { value: ['de'] });
    },
    headers: {
      'Accept-Language': 'de',
    },
});