Jitsi Meet Electron

Excellent voice and video call software, for 1-on-1 or group. With the desktop app, it's possible to keep a floating window, just like Skype (it's one of the very few open-source video call softwares that include this very rare feature). The network quality is awesome and there is a very reliable indicator with lots of technical infos if you want to check, or just look at the quality percent and color of the indicator. End-to-end encrypted voice and video calls are also implemented in beta, a worldwide first for an in-browser software using WebRTC (and insertable streams - which work only on Chrome browsers for the moment). Jitsi Meet can also share the screen, but does not allow for remote desktop control currently due to a security exploit, but it could in the past, but only when the host was using the desktop app, not the web app. Also, of course, the software does not allow for unattended access, the use case is rather for infrequent assistance with the assisted person online to discuss the issue.

Basically, this is an excellent replacement for Skype.