As the Skype Classic app will soon be deprecated in November, Microsoft is currently working hard to bring all of its features to its new modern Skype app. Split View support, a feature that many power users enjoyed on Skype Classic, is now available in the latest preview version of Skype for Windows 10.
Split View mode is now available on our latest Skype for Windows 10 Insiders builds, 18.104.22.168/22.214.171.124! Try it out and send us your feedback! For more info on Skype for Windows 10 Insiders visit https://t.co/OnxwFfDOhV. ^KB
— Skype Insider (@SkypeInsider) October 22, 2018
To be clear, Skype for Windows 10 is the new Microsoft Store app that replaced the old UWP version in the Windows 10 October Update. The app looks exactly like the cross-platform Skype v8 app that is also available as a standalone app on Windows, but Skype for Windows 10 can take advantage of OS-integrated features like Windows Share Charm and MyPeople.
Split View is currently enabled in Skype for Windows 10 version 126.96.36.199, and you'll need to join the Skype App Preview program in the app's Settings to get this build. To try the feature, you’ll have to click the “…” button and then select “Enable Split View mode.” Once you do that, the right panel of Skype for Windows 10 will disappear, resulting in a narrower window that looks quite similar to the Skype Classic app. From then, you can double click on any conversation you want, and they will be opened in separate windows.
In case you closed the list of chats by mistake, every chat window actually has an “Open recent chats” button on the top left corner, which will bring the main Skype window back. If you don’t like it, you can disable Split View anytime you want by clicking the same "..." button in the main window.
Overall, the come back of Split View should be good news for fans of Skype Classic, but Skype for Windows 10 is still not as flexible as the legacy desktop app: It's still not possible to customize notifications, or resize the window to make it as narrow as possible. However, the Skype team is really listening to the community, and you can share your feedback on Microsoft's Community website or the new Skype Ideas website.