polyfill window.fetch

[bahmutov]

We only spy / stub XMLHttpRequest methods, so the new window.fetch calls are "invisible" to Cypress. We recommend our users delete / polyfill window.fetch to drop down to use XMLHttpRequest. It would be nice to do this for users automatically, behind a flag.

Once full network stubbing lands, we can remove this polyfill

[cypress-bot]

The code for this is done in cypress-io/cypress#7597, but has yet to be released.
We'll update this issue and reference the changelog when it's released.

[cypress-bot]

Released in 4.9.0.

This comment thread has been locked. If you are still experiencing this issue after upgrading to
Cypress v4.9.0, please open a new issue.