Apps sometimes open in background

Can’t quite figure exactly why and when, but more often than not if you tap on an app icon in the drawer it would open in the background, i.e. won’t appear on the screen immediately, unless you press the app icon again. When it does open in the background, swiping to the list of running apps and opening it there works. Is that by design? Is that something broken on my end?

Is it possible that what you describe is related to this bug description ?

No, not exactly. In my case nothing happens at all on the screen. If you press any app icon the second time, it would switch to that app (open it in foreground). I think this behavior only affects Android apps, but I haven’t had much time to figure out a pattern what triggers it. I semi-vaguely remember it only started happening several days into a fresh install. Or maybe not. Don’t want to reflash the phone just to check for that now.

In my case it happens every time if I open the app drawer from the lockscreen.