Potential evidence of the Google Pixel Fold has been spotted within the Android 13 beta. Even if it doesn't directly link to a Google foldable, it is at least proof that the company's starting to think how to deal with folding phones within Android natively.
Found by 9to5Google, changing the DPI of a phone within the Android 13 Developer Preview 1 (a developer-only option) allowed it to make a Google Pixel 4 XL show the tablet version of the Android interface, including a taskbar and a new layout. These layouts are retained when swapping back and forth between the two modes, aside from a few icons that could be suffering from bugs.
This is similar to how the Samsung Galaxy Z Fold 3 and previous Folds work with their dual home screens. While you can opt to have the inner display match the outer display's layout (which is how the Oppo Find N does it), by default you have two separate arrangements of apps and widgets.
It shows that Google has been putting a lot of thought into how to better cater for foldable devices as well as tablets. If the Pixel Fold (also potentially called the Pixel Notepad) is indeed on the way in the near future, then this is key groundwork to do.
Google already went some way to better cater for tablets through the Android 12L update. Making its OS natively work better on larger screens would be a key part of getting ready for a foldable device too. In fact, there's no reason why Google couldn't implement this dual home screen system in Android 12L before it gets its final release.
There's still no sign of a specific launch period for the Pixel foldable. There are rumors that it will be well-priced for a foldable at around $1,400, could use a squarer Find N-style design, and may feature a single rear 12MP camera along with two 8MP front cameras. If this phone is indeed debuting in 2022, hopefully we'll get many more concrete leaks to fill in the blanks for us soon.