Last time I decided to use Ubuntu 17.10. When I installed Skype from official site of Skype (I downloaded the .deb package) I can do almost everything without one important feature for me. I can't share my screen while I am talking with somebody. On Windows that was working perfectly, on Ubuntu I don't even see such a option.
My friend has the same version of Ubuntu, GNOME and Skype. He can use that feature. I can't and I can't figure out why.
Best Answer
If you use Wayland (Ubuntu 17.10) and latest version (v8.11.0.4) of skypeforlinux screen sharing is not working.
In order to have screen sharing working you can switch to Xorg as explained here.
Otherwise you can use Google Hangout, where you can even share windows.