Calls to Firestore with Firebase JS API 7.x and 8.x are blocked

[GerroDen]

Hello,

I like to use the plugin to mock calls to endpoints that would result in unnecessary billings during development. It works great. The only issue i currently have is, that we use an older Firebase JS SDK (7.24) which we unfortunately cannot upgrade quickly. With some testing i can narrow it down that it works with disabled Mokku and it would work with Firebase JS SDK v9. It does not work with v7 and v8, so it seems Firebase changed some ways how it works.

I get the following error in the console when I try to initialize the Firebase application:

@firebase/firestore: Firestore (7.24.0): Could not reach Cloud Firestore backend. Connection failed 1 times. Most recent error: FirebaseError: [code=unavailable]: The operation could not be completed
This typically indicates that your device does not have a healthy Internet connection at the moment. The client will operate in offline mode until it is able to successfully connect to the backend.

In Mokku logs i can see the calls with HTTP-Code -1. That seems odd to me. Maybe that's a hint. Firestore does quite different HTTP calls anyway.

When I disable Mokku within the extension, everything works fine. Maybe we can find a solution within the extension?