can i "edit" the headers of a incoming request? i want to see if i can read a cookie and write it into a header so that some other feature / interceptor can work with it i get that i need to do somthing like

receivePipeline.intercept(ApplicationCallPipeline.Features) {
    val headers = call.requestheaders
    
    //TODO: add header
}

but how would i copy the request or be able to get a mutable version of the headers ?

You can instead, write an interceptor to read cookie header, find what you need and add it as an attribute to call.attributes map. And then your next feature/plug-in can find key and work with its value from call.attributes. I think that should work.

sadly i cannot modify the other feature too much (at least without significantly more effort) which is why i am trying to hack around it