Option to use `fetch` instead of `XMLHttpRequest` for polling

[matthiasgeihs]

Is your feature request related to a problem? Please describe. Some environments don't support XMLHttpRequest, but support fetch. (e.g., MetaMask Snaps)

Describe the solution you'd like It would be great if there was an option for using fetch instead XMLHttpRequest.

Describe alternatives you've considered There seems to be a way to solve this problem via a postinstall patch (as described in the article linked above), but native support would be favored.