When Google pushed out the new "fully gestural navigation" mode in Android Q Beta 3, regardless of your general opinion when it came to the new navigation system, there was one objective drawback: it broke screen pinning. Well, Google has fixed this particular issue in typical Google fashion as of Beta 4, disabling screen pinning entirely if you enable the new gesture navigation system.

Screen pinning, for those unaware, allows you to lock your phone to a specific application, keeping it open to prevent kids from accidentally leaving it, or snooping friends from digging around.

The previous issue stemmed from the fact that you couldn't perform the navigational key combination required to exit the pinned mode while in fully gestural navigation. (Typically, you have to hold the back and home buttons at the same time to unpin an app, but fully gestural means no navigation buttons.) When you enabled pinned mode on Android Q Beta 3, although you could navigate to the home screen in a pinned app (a problem in itself) you couldn't launch apps, open the status bar, open the multitasking menu, or do anything, really.

You could easily get trapped in a pinned mode, requiring a reboot.

Android Q Beta 4 on the Pixel 3a in two-button gesture navigation mode (left) and fully gestural navigation mode (right). Note the absence of "Pin" on the right. 

As of Android Q Beta 4, pinning apps appears to be entirely disabled via the multitasking menu if you enable the new full gesture navigation mode. The option to do so is removed until you switch to either the two or three-button navigation modes.

Hopefully, Google can come up with another system or gesture to exit pinned mode in the new fully gestural navigation system. If it's going to push this type of navigation on us in the future, it will need to maintain feature parity, and plenty of people will miss screen pinning.

Mishaal Rahman has spotted a string while tearing down Android Q Beta 4 that is explicit in describing how screen pinning will eventually work when in gesture mode. Based on the discovery, a gesture-based solution to exiting screen pinning without the navigation buttons is still being worked on, it just hasn't been implemented yet.