Oppo
Allow Display Over Other Apps auf Oppo
Apps that need to appear on top of your current screen, such as chat bubbles, screen recorders or call widgets, rely on a system permission called Display over other apps. On Coloros this permission is managed per app and is often turned off by default for anything installed outside the preloaded app set.
If an app cannot draw over other apps, its floating window, bubble or overlay simply never appears, even though the app itself runs normally in the background. This is different from a notification problem: the app is active, but it is missing the specific permission to render above other windows.
To check or change this permission, go to Tap on Settings ➔ Tap on App management ➔ Tap on Display over other apps ➔ Turn On/Off an App. This list shows every installed app together with a toggle for this exact permission.
Turn the toggle on for any app whose overlay, chat head or floating tool you want to see on top of other screens. Turn it off if an app keeps showing unwanted popups or overlays while you use something else.
If an app still fails to overlay after enabling this setting, check whether battery optimization or background restrictions are limiting the app further, since both settings work together to control what an app can do while not in focus.