In 2018, Microsoft introduced a multitasking feature called "Windows Timeline" that lets you view a schedule of activities you've done in Windows 10, including webpages you've visited, documents you've created / opened, photos you've added, and others.
Windows Timeline, which you can access using the Win + Tab shortcut, records and organizes the activities you do on your computer and lets you sync content with other devices. For example, you can start a task (open a webpage or document) on a device (for example a PowerPoint presentation) and switch devices and continue your project from where you left off.
With Windows 10 Sun Valley Update, Microsoft is withdrawing support for device synchronization in the Timeline, which means that users will not be able to open a webpage or document on a device and switch devices in the media.
In the release notes for Build 21359, Microsoft noted that Windows 10 activity history synchronization support is no longer available for those with a Microsoft account. It will still work if you use AAD-linked accounts, but you can no longer synchronize activities across all devices when they are linked to a Microsoft account.
The schedule and local activity history will remain in Windows 10, which means that the Timeline is not interrupted, at least for now.
If you want to view web history on your devices, the Microsoft products recommends that you enable sync support in Edge or other browsers.
Source of information: bleepingcomputer.com