http://isdb4l77sjqoy2qq7ipum6x3at6hyn3jmxfx4zdhc72ufbmuq4ilwkqd.onion/docs/guide/audio-video-calls.html
Accepting the calls When there is an incoming call you have three options: accept: to connect the call reject: to reject the call, without notifying the caller. ignore: to temporarily dismiss the call, but in a way that it can be accepted later, if the caller is still waiting, via the Accept call message in the conversation with this contact. There is no time limit that the call invitation can remain active - as long as the caller is still waiting, you can accept the call...