Is there any setting to enable for WebRTC encryption (DTLS, SRTP)

Is there any setting to enable for WebRTC encryption (DTLS, SRTP) or does this happen automatically when it’s negotiation with the coturn server?

WebRTC is always encrypted. It is a protocol that requires and brings encryption by default.
Browser won’t even enable the WebRTC API if they are not currently in an HTTPS page.

Thanks for confirming this.