I have just returned to testing linphone (after getting twinkle to work as well), and I have hit another problem.
I can make outgoing calls, but I cannot answer incoming calls. Could that be another missing icon? When I make an incoming test tool, linphone plays the ringtone, but I can't see any change in the GUI, nor any way to answer the call. I have just posted a message to the linphone mailing list linphone-us...@nongnu.org