The feature was uncovered by Windows Central. It’s unclear how far developed this new “Tabbed Shell” is or whether it’ll ever see the light of day. For now it’s an internal engineering concept which could be introduced in a future version of Windows 10.
Tabbed Shell derives from one of the most upvoted pieces of feedback in Windows 10’s Feedback Hub: many users want tabbed windows to be added to File Explorer. Windows customers have long requested Microsoft implement a tab strip in its file browser, avoiding the need to open multiple windows when several directories are required at once.
Microsoft has previously acknowledged the feedback but still shows no signs of acting on it and bringing tabs to File Explorer. Tabbed Shell suggests it’s about to go even further than the feedback though, instead enabling tabs for all windows.
The mock-ups created by Windows Central show how this would work. Every window’s title bar would include a tab strip, visually similar to the one used in Microsoft’s Edge web browser. When you open a new instance of the app, it would show up in the title bar, making it easier to stay organised when multiple windows are open.
It can be assumed Microsoft will implement all the tabbed UI fundamentals available in web browsers. You’d be able to pull tabs out to pop them into a new window, push windows back onto a tab stack to close them and take advantage of keyboard shortcuts to quickly navigate between app instances. The result would be a power user’s dream, although it could end up alienating users unfamiliar with the transformation of windows into tabs.
This potential issue is made more serious by a complication with the current concept. Because Microsoft cannot make such a dramatic change to Windows’ core app border without impacting current programs, developers would need to adjust their apps for Tabbed Shell to work properly. Older apps will end up with aesthetic abnormalities that could confuse users.
A properly optimised app would take full advantage of the tabbed layout and have complete visual polish like a web browser. In contrast, apps that haven’t been updated would have a double title bar. As seen in the mock-up, the operating system would be forced to place the tab strip above the existing title bar, causing the minimise, maximise and close buttons to be duplicated.
There are a couple of ways this could be avoided. The first and most obvious is to only enable the tab strip on fully optimised apps. This would prevent the visual issues from appearing but could hinder adoption of the Tabbed Shell. Alternatively, Microsoft could find a way of intelligently hiding the close buttons in the original window instance, although this may not be possible for apps with modified title bar styles.
Microsoft is still in the early stages of planning this feature so it’s likely to change significantly before it’s unveiled. It could be cancelled before ever reaching a public build. Tabbed Shell addresses one of the most popular requests for Windows 10’s core UI so it’s probable it’ll eventually make an appearance. As per Windows Central’s report, it’s unlikely to arrive before the Windows 10 “Redstone 4” update in 2018.
