I found some old threads here that mentioned this issue. The solution was to disable WebRTC in the user management. Sadly, I don’t see it in my freshly installed v16.
Main questions are:
Does it take system resources (I don’t see double users though, only extensions)?
Do I need WebRTC if I only use SIP (not planning to use browser)?
How to disable those 99 extension if it doesn’t harm the system?
There is no issue with system resources that I can think of with the webrtc module, but if you want to remove the module entirely, you can in Module Admin.
The pjsip endpoint it controlled in User Management. Edit either the user or the group, under the UCP tab, and Phone sub-tab.