Memory leak Realme RMX3501

Question

There are no memory leaks on android 11 Realme RMX3501 (C31), and there are no memory leaks on other devices that I have.On 13 android with RMX3501_13.F.54 firmware, activity is constantly leaking.

The activity leaks every time onDestroy is called Below is an example. What can it be related to?

 │ GC Root: Global variable in native code
 │
 ├─ android.database.ContentObserver$Transport instance
 │    Leaking: UNKNOWN
 │    Retaining 822 B in 9 objects
 │    ↓ ContentObserver$Transport.mContentObserver
 │                                ~~~~~~~~~~~~~~~~
 ├─ android.view.WindowManagerImpl$ThreeFingerObserver instance
 │    Leaking: UNKNOWN
 │    Retaining 286 B in 8 objects
 │    ↓ WindowManagerImpl$ThreeFingerObserver.this$0
 │                                            ~~~~~~
 ├─ android.view.WindowManagerImpl instance
 │    Leaking: UNKNOWN
 │    Retaining 78 B in 3 objects
 │    mContext instance of android.app.ContextImpl
 │    ↓ WindowManagerImpl.mContext
 │                        ~~~~~~~~
 ├─ android.app.ContextImpl instance
 │    Leaking: YES (ContextImpl.mOuterContext is an instance of ru.price.mobilescoutnative.camera.completephoto.
 │    CompletePhotoActivity with Activity.mDestroyed true)
 │    Retaining 6,9 kB in 104 objects
 │    mOuterContext instance of ru.price.mobilescoutnative.camera.completephoto.CompletePhotoActivity with mDestroyed =
 │    true
 │    ↓ ContextImpl.mOuterContext
 ╰→ ru.price.mobilescoutnative.camera.completephoto.CompletePhotoActivity instance
    Leaking: YES (ObjectWatcher was watching this because ru.price.mobilescoutnative.camera.completephoto.
    CompletePhotoActivity received Activity#onDestroy() callback and Activity#mDestroyed is true)
    Retaining 16,0 MB in 836 objects
    key = 0b60122b-03ad-4fc0-bfc3-6b60e1b5b406
    watchDurationMillis = 59595
    retainedDurationMillis = 54595
    mApplication instance of ru.price.mobilescoutnative.App
    mBase instance of androidx.appcompat.view.ContextThemeWrapper

There are no memory leaks on android 11 Realme RMX3501 (C31), and there are no memory leaks on other devices that I have.

UPD: I Created a simple test project https://github.com/Vanilla1999/Test

How to reproduce the error:

1. click button
2. click "back" button Result:

1. click button
2. click button

Answer 1

The above memory leak is releated to the modification in Android 13 ROM by the manafuctor OPPO.

They created a instance of non-static inner class ThreeFlingerObserver in WindowManagerImpl and register it to the ContentResolver but never unregister it, which will lead to the memory leak and oom at last.