I am using native alpha to create shortcuts to my frequently used web apps and to keep them as separate apps for use with the android app switcher (swipe up from bottom of screen to switch to different apps). One thing I noticed is that on apps that have the restrict access enabled, you can see the thumbnail of the app's screen even after the app was closed. When you go to open said app, the pin/fingerprint then shows up and the screen in blacked out like you would expect.
Not sure if this is a limitation of how android handles things, but would it be possible to enable the restriction or black out the screen at the moment the app is left/closed so the app switcher doesn't have access to the thumbnail of the apps screen?