One of the most popular feature requests (more than 20,000 votes) for Windows 10 is tabs in File Explorer. Microsoft has resisted adding tabs to File Explorer and apps in general for years, after originally introducing tabs in Internet Explorer 6 with a toolbar extension back in 2005. That resistance is about to change, in a big way. Microsoft is planning to add tabs to apps in Windows 10, allowing you to group together apps in a better way.

Windows 10 testers will first start testing what Microsoft calls “Sets” in the coming weeks, and the tab integration will be initially limited to Windows 10’s special Universal Windows Apps. Microsoft is planning to get as much feedback on the new feature as possible, before tweaking it and making it available to everyone. The software giant isn’t committing to a specific timeline for tabs.

The idea behind the tabs feature is revealed in the name. “Sets” is designed to group a particular task together. Let’s say you’re working on a Word document and you need to research data on the web or grab notes from an app, you could create Sets (or tabs) of these tasks in a single window. It’s designed to keep that browser tab you’re using to research work separate from the other one you’re using to watch YouTube, and to have tabs in a single window that are relevant to the tasks you’re performing in Windows.

I got a chance to see some early concepts for Sets earlier this month, and the feature seems like something that should have just been part of Windows 10 all along. It looks natural, and I can see the benefits even if it’s not something I’ll use all the time. Microsoft has some ambitions for Sets that go further than just the Windows desktop, though.

Like its Timeline feature of Windows 10, which will be available to testers in the next build, Sets are designed to let you carry on working on or from a mobile device By grouping tasks into these Sets, Microsoft is aiming to let iPhone and Android users start Sets and then resume them on a PC or vice versa. It’s a logical extension of Timeline, which groups together your apps in a similar way so you can resume them across mobile and PCs.

Microsoft is planning to extend these tabs to standard desktop apps like File Explorer or Notepad, and eventually to apps that have custom titlebars like Photoshop. An updated desktop version of Office will support Sets early next year. Microsoft’s real challenge with Sets will be convincing developers to embrace them on the mobile side, so apps can resume easily. That’s not an easy thing to solve, so I’d expect that type of experience will be limited to Office and Edge mobile initially.

The experience of Sets also includes a universal search feature and a new blank tab is identical to the new tab interface in the Microsoft Edge browser. Microsoft is essentially extending Edge into the shell of all apps in Windows 10, a move that will generate a lot of discussion. Microsoft ended up in court with the US Department of Justice back in 2001 over bundling Internet Explorer directly into Windows. Either way, computing and competition has changed a lot since then, and without some type of web functionality this tabs interface wouldn’t work efficiently.

Microsoft is planning to open tabs up to Windows 10 testers in the coming weeks, and the company will be testing it with a small subsection of testers initially. The plan is to get specific feedback before letting all Windows 10 testers get a closer look at the new tabs interface.