Note experimental room version ID
@@ -589,6 +589,7 @@ An unstable feature flag is not required due to this proposal's requirement
of a new room version. Clients can check for a room version that includes
knocking via the Client-Server API's [capabilities
endpoint](https://matrix.org/docs/spec/client_server/r0.6.1#get-matrix-client-r0-capabilities).
+Experimental implementation should use `xyz.amorgan.knock` as a room version identifier.
The new endpoints should contain an unstable prefix during experimental
implementation. The unstable counterpart for each endpoint is:
