Can Ambassador handle CORS requests?
Turns out, by specifying headers: "Content-Type" in the cors configuration, things just started to work. Apparently that's not as optional as I thought.
So this is now my module:
getambassador.io/config: |--- apiVersion: ambassador/v1kind: Modulename: ambassadorconfig: service_port: 8080 cors: origins: [my domain here] headers: "Content-Type" credentials: true