Flurl.Http sends in every Request the following Header:

I have recently updated from the old IFlurlClientFactory to the new IFlurlClientCache and thus applied all the required changes.

What we have implemented currently is something like this: https://v3.flurl.dev/docs/configuration/#httpclientfactory with the CustomHttpClientFactory being a BearerTokenManagingHttpClientFactory which inherits DefaultHttpClientFactory and overrides CreateHttpClient() and CreateMessageHandler() methods. It adds some headers in the override of CreateHttpClient and returns something called BearerTokenMessageHandler object in the override of CreateMessageHandler. BearerTokenMessageHandler itself inherits DelegatingHandler.