Install WebRTC
At first, be sure that you have enabled WebRTC in your web browser.
about:config
media.peerconnection.enabled = true
Update the system and install packages
apt-add-repository ppa:strukturag/spreed-webrtc apt-get update && apt-get install spreed-webrtc
systemctl status spreed-webrtc
active (running)
spreed-webrtc-server -v
Version 0.28.1
Add webrtc to services
vi /etc/services
webrtc 8080/tcp # nextcloud
netstat -apt | grep webrtc
tcp 0 0 localhost:webrtc *:* LISTEN 13197/spreed-webrtc