Microsoft pulls Windows Sets “tabbed windows” feature from next release
First previewed last November, Sets, a new Windows interface feature that will make every window into a tabbed windows, has been removed from the latest Insider Preview build of Windows 10. Moreover, the Verge is reporting that the feature won't be coming back in this year's next major update, due in October.
This marks the second time that Sets have been included in a preview release, only to be removed at a later stage prior to the release of an update. When first announcing Sets, Microsoft was very careful to note that it wasn't promising Sets for any particular release—or possibly even ever, given the complexities of application compatibility and uncertainty about how people will actually use the feature.
The promise of Sets is certainly high. Putting tabs in every window is a way of solving certain long-standing requests such as the demand for tabs in Explorer, but Sets went far beyond this, allowing sets of different applications to be grouped together with tabs to switch them. As such, they became a way of managing one's workspace, allowing you to combine, say, a Word window with a school paper with the online resources that you're using to write the paper.