//
//	https://pkg.go.dev/net/http#ResponseWriter
//	https://pkg.go.dev/net/http#example-ResponseWriter-Trailers
const TrailerPrefix = "Trailer:"

// finalTrailers is called after the Handler exits and returns a non-nil
// value if the Handler set any trailers.
func (w *response) finalTrailers() Header {
	var t Header
	for k, vv := range w.handlerHeader {
		if kk, found := strings.CutPrefix(k, TrailerPrefix); found {
			if t == nil {