Microsoft is releasing a big update to Windows 10 testers today, just before the new year begins. The software giant is rolling out Windows 10 build 17063 to Fast Ring testers, complete with the Timeline feature and the new window tabs the company revealed last month.

Timeline was originally supposed to ship with the Fall Creators Update, allowing Windows 10 machines to resume apps and activities across devices. Timeline will let you effectively pick up where you left off if you're switching between Windows 10 devices. Thanks to Cortana integration, this will even extend to some Microsoft apps on iOS and Android eventually. It's a quick way to move from one machine to another, much like Apple's continuity feature in iOS and macOS.

In this latest build, Timeline can be accessed through the usual Task View area in Windows 10. Timeline provides a visual overview of all recent activities, including apps that were running on a Windows 10 PC at a particular time. It’s similar to the recent tabs feature in Chrome, where you can resume sets of tabs you were viewing on another device. Cortana will also prompt Windows 10 users to resume these activities thanks to the Timeline feature.

Alongside Timeline, Microsoft is also testing out Sets — its tabbed window feature. Microsoft admits it may end up calling it something else by the time it ships, and the company is only testing Sets with a limited number of Windows Insiders today. Sets add tabs to windows so that activities can be grouped into a single interface. It’s very much tabbed browsing but for every Windows 10 app. Only Universal Windows Apps will be supported initially, with this extending to Office and win32 apps next year.

Microsoft has also added a number of new features elsewhere in this latest test version of Windows 10. Microsoft Edge picks up an updated dark theme with better contrast and more of the company’s Fluent Design system in action. Gestures have also been improved for precision touchpads, allowing you to pinch and zoom on a trackpad and more.

Cortana is also getting a new design in this latest build, with a new Organizer home. You can manage lists and reminders from this interface, and access all the skills available in Cortana. Cortana even has a tabbed view to better separate content, and you can now use the digital assistant to control music playback through Spotify.

Microsoft is also bringing more of its Fluent Design to Windows 10. The taskbar, action center, clock & calendar, and share UI have all been updated with subtle changes. Even the My People section of Windows 10 is seeing some tweaks, with a drag and drop rearrange feature and the ability to decide how many people are pinned to the taskbar. Windows 10’s settings section is also getting redesigned to make it easier to find individual settings.

This latest Windows 10 test build also includes more DPI improvements. Microsoft has been battling for years to fix DPI scaling issues in Windows, and the company is now introducing a new setting in the display settings to let Windows automatically fix scaling for apps. This is helpful if you remote into your PC, or if you dock your laptop to a monitor and the resolution and scaling changes. You can also override DPI settings per app. Microsoft’s new Windows 10 build includes a lot more changes, and the full list is available at the company’s blog post.