I came across this section of the documentation that you're talking about recently: #5444

My reason for searching for this part of axios was I'm looking at recreating the client side half of this example in the browser using javascript: https://github.com/libp2p/go-libp2p-http

tr := &http.Transport{}
tr.RegisterProtocol("libp2p", p2phttp.NewTransport(clientHost))
client := &http.Client{Transport: tr}
res, err := client.Get("libp2p://Qmaoi4isbcTbFfohQyn28EiYM5CDWQx9QRCjDh3CTeiY7P/hello")

What that example is doing is tunneling an HTTP request over a p2p network, using the libp2p protocol. It takes the Go http package and registers a "Transport" using a function of the package called NewTransport() which returns a Roundtripper struct described here: https://github.com/libp2p/go-libp2p-http/blob/master/p2phttp.go#L82

When I was looking for an equivalent to the Go http.client.Transport in the Axios library is how I came across he aforementioned commit here.

The commit describes axios.request('url', config), config. transport, as type any. So as you pointed out, it's not actually part of the AxiosRequestConfig

I hope this is a feature of the axios lib; I'll look for other means of achieving what I want. Compiling the example client to WASM is an option I think but would rather have a JS native way to do this.