It'd be really nice if libp2p could make these keys case-insensitive or throw when an unknown key is encountered - webRTCStar vs WebRTCStar is easy to get wrong.

We will work on improving the config per libp2p/js-libp2p#576. It will probably change a lot the way we config libp2p. But referencing so that we have this in attention

I just noticed in our config docs that we have this:

const transportKey = WebRTCStar.prototype[Symbol.toStringTag]

Should we use it here to avoid confusions on where the naming comes from?

Actually I'm not sure if that makes it any clearer. It would be vastly preferable to be able to just use [WebRTCStar.tag] the same as the peer discovery config key.

We should rething that in the config issue for libp2p. From what I know, the tag was added for the discovery side of things. The transports do not include it, except for webrtc-star, as it is both transport and discovery.
Anyway, we will look into it in a future libp2p release

Do we want to remove discovery?

From the old instructions you have to new up a WebRTCStar instance to get the discovery property, but now that throws an error about providing an upgrader.

Could you make a suggested change to correct the config here please?

https://github.com/libp2p/js-libp2p/blob/v0.27.8/doc/CONFIGURATION.md#setup-webrtc-transport-and-discovery

 peerDiscovery: {
   [WebRTCStar.tag]: {
     enabled: true
   }
}

FYI I also did #3092 a while ago that uses the tag's instead of the string to avoid errors like the case sensitive that you mentioned earlier, but this is only available for discovery.

also PRd libp2p to use the tag in this missing doc: libp2p/js-libp2p#713

Is #3092 ready for review/merging? It's been draft for ages.