A patent application published today adds more fuel to the fire about the possibility of a new hybrid dual-screen Microsoft Surface device that blurs the lines between phone and tablet.

The patent filing is for a “hinged device” with a “first and second portion” that includes a “flexible display.” It would sport a hinge in the middle, similar in appearance to the one on the Surface Book, as well as familiar smartphone components like a bezel and camera.

The inventor listed on the document is Kabir Siddiqui, who has been named on previous patent documents related to a foldable Surface device. He’s also credited with inventing features like the Surface kickstand and camera.

The patents represent one of the clearest signs yet that Microsoft has shown interest in building a “new and disruptive” category that includes elements of a smartphone, tablet and computer all in one. Rumblings of a new Surface phone-like device, under the codename Andromeda, have persisted for years, though the company has yet to confirm such a plan.

Microsoft representatives declined to comment on the patent filing.

Diehard Windows Phone fans are eager to see a new mobile offering from Microsoft, and they even circulated a change.org petition in July after news reports indicated that the device may be on hold indefinitely.

Plans for the device reportedly came together under the direction of Terry Myerson, who left the company following a reorganization earlier this year. New leadership could take the device in a new direction or discard it entirely.

The patent filings shed little light on the current status of the device, as the original application dates back to the summer of 2017. Microsoft just held a big hardware event last week, which included a new Surface Headphones product, as well as the next generation of the Surface Pro and Surface Laptop but nothing about a foldable phone/tablet.

Microsoft has largely retreated from the smartphone hardware market when Windows Phone failed to catch on. Microsoft has spent the last few years shifting its mobile strategy to focus on breaking down the walls between devices and unifying the Windows experience between PCs and smartphones on competing operating systems. Apps like Microsoft Launcher and tools like Project Rome exemplify Microsoft’s new mobile strategy.