memory leak when there's an active navigation and the NavFragmentActivity is exited

[confused-again]

description:

build and run the provided navigation-sample project,
launch the demo NavFragmentActivity
click 'set destination' button and enter a city that's accessible (eg. Toronto)
allow the navigation simulation to start
go back (from the system action bar)
observe a memory leak.

question:
is this a valid memory leak detected by leakCanary? is there a workaround for this within the application or does the library need to be fixed?

logs:

01-08 11:41:30.857 24515 25171 D LeakCanary: ====================================
01-08 11:41:30.857 24515 25171 D LeakCanary: HEAP ANALYSIS RESULT
01-08 11:41:30.857 24515 25171 D LeakCanary: ====================================
01-08 11:41:30.857 24515 25171 D LeakCanary: 1 APPLICATION LEAKS
01-08 11:41:30.857 24515 25171 D LeakCanary:
01-08 11:41:30.857 24515 25171 D LeakCanary: References underlined with "~~~" are likely causes.
01-08 11:41:30.857 24515 25171 D LeakCanary: Learn more at https://squ.re/leaks.
01-08 11:41:30.857 24515 25171 D LeakCanary:
01-08 11:41:30.857 24515 25171 D LeakCanary: 3009052 bytes retained by leaking objects
01-08 11:41:30.857 24515 25171 D LeakCanary: Signature: 1c492f6be9580b9a9d8b8d1c3b7b6439a9fab1b0
01-08 11:41:30.857 24515 25171 D LeakCanary: ┬───
01-08 11:41:30.857 24515 25171 D LeakCanary: │ GC Root: Input or output parameters in native code
01-08 11:41:30.857 24515 25171 D LeakCanary: │
01-08 11:41:30.857 24515 25171 D LeakCanary: ├─ com.google.android.libraries.navigation.internal.fs.s instance
01-08 11:41:30.857 24515 25171 D LeakCanary: │ Leaking: UNKNOWN
01-08 11:41:30.857 24515 25171 D LeakCanary: │ Retaining 30 B in 1 objects
01-08 11:41:30.857 24515 25171 D LeakCanary: │ ↓ s.c
01-08 11:41:30.857 24515 25171 D LeakCanary: │ ~
01-08 11:41:30.857 24515 25171 D LeakCanary: ├─ com.google.android.libraries.navigation.internal.in.ac instance
01-08 11:41:30.857 24515 25171 D LeakCanary: │ Leaking: UNKNOWN
01-08 11:41:30.857 24515 25171 D LeakCanary: │ Retaining 1.7 kB in 60 objects
01-08 11:41:30.857 24515 25171 D LeakCanary: │ ↓ a.e
01-08 11:41:30.857 24515 25171 D LeakCanary: │ ~
01-08 11:41:30.857 24515 25171 D LeakCanary: ├─ java.util.concurrent.ConcurrentHashMap instance
01-08 11:41:30.857 24515 25171 D LeakCanary: │ Leaking: UNKNOWN
01-08 11:41:30.857 24515 25171 D LeakCanary: │ Retaining 1.4 kB in 48 objects
01-08 11:41:30.857 24515 25171 D LeakCanary: │ ↓ ConcurrentHashMap[key()]
01-08 11:41:30.857 24515 25171 D LeakCanary: │ ~~~~~~~
01-08 11:41:30.857 24515 25171 D LeakCanary: ├─ com.google.android.libraries.navigation.internal.in.a$a instance
01-08 11:41:30.857 24515 25171 D LeakCanary: │ Leaking: UNKNOWN
01-08 11:41:30.857 24515 25171 D LeakCanary: │ Retaining 17.2 kB in 261 objects
01-08 11:41:30.857 24515 25171 D LeakCanary: │ ↓ a$a.b
01-08 11:41:30.857 24515 25171 D LeakCanary: │ ~
01-08 11:41:30.857 24515 25171 D LeakCanary: ├─ java.util.concurrent.Executors$RunnableAdapter instance
01-08 11:41:30.857 24515 25171 D LeakCanary: │ Leaking: UNKNOWN
01-08 11:41:30.857 24515 25171 D LeakCanary: │ Retaining 17.1 kB in 260 objects
01-08 11:41:30.857 24515 25171 D LeakCanary: │ ↓ Executors$RunnableAdapter.task
01-08 11:41:30.857 24515 25171 D LeakCanary: │ ~~~~
01-08 11:41:30.857 24515 25171 D LeakCanary: ├─ com.google.android.libraries.navigation.internal.bo.ao instance
01-08 11:41:30.857 24515 25171 D LeakCanary: │ Leaking: UNKNOWN
01-08 11:41:30.857 24515 25171 D LeakCanary: │ Retaining 17.1 kB in 259 objects
01-08 11:41:30.857 24515 25171 D LeakCanary: │ ↓ ao.a
01-08 11:41:30.857 24515 25171 D LeakCanary: │ ~
01-08 11:41:30.857 24515 25171 D LeakCanary: ├─ com.google.android.libraries.navigation.internal.zd.bw instance
01-08 11:41:30.857 24515 25171 D LeakCanary: │ Leaking: UNKNOWN
01-08 11:41:30.857 24515 25171 D LeakCanary: │ Retaining 17.1 kB in 258 objects
01-08 11:41:30.857 24515 25171 D LeakCanary: │ ↓ d.value
01-08 11:41:30.857 24515 25171 D LeakCanary: │ ~~~~~
01-08 11:41:30.857 24515 25171 D LeakCanary: ├─ com.google.android.libraries.navigation.internal.cq.bw instance
01-08 11:41:30.857 24515 25171 D LeakCanary: │ Leaking: UNKNOWN
01-08 11:41:30.857 24515 25171 D LeakCanary: │ Retaining 17.1 kB in 257 objects
01-08 11:41:30.857 24515 25171 D LeakCanary: │ ↓ bw.b
01-08 11:41:30.857 24515 25171 D LeakCanary: │ ~
01-08 11:41:30.857 24515 25171 D LeakCanary: ├─ com.google.android.libraries.navigation.internal.nv.g instance
01-08 11:41:30.857 24515 25171 D LeakCanary: │ Leaking: UNKNOWN
01-08 11:41:30.857 24515 25171 D LeakCanary: │ Retaining 1.3 kB in 40 objects
01-08 11:41:30.857 24515 25171 D LeakCanary: │ ↓ g.a
01-08 11:41:30.857 24515 25171 D LeakCanary: │ ~
01-08 11:41:30.857 24515 25171 D LeakCanary: ├─ com.google.android.libraries.navigation.internal.ov.e instance
01-08 11:41:30.857 24515 25171 D LeakCanary: │ Leaking: UNKNOWN
01-08 11:41:30.857 24515 25171 D LeakCanary: │ Retaining 352 B in 11 objects
01-08 11:41:30.857 24515 25171 D LeakCanary: │ ↓ e.g
01-08 11:41:30.857 24515 25171 D LeakCanary: │ ~
01-08 11:41:30.857 24515 25171 D LeakCanary: ├─ com.google.android.libraries.navigation.internal.ov.d instance
01-08 11:41:30.857 24515 25171 D LeakCanary: │ Leaking: UNKNOWN
01-08 11:41:30.857 24515 25171 D LeakCanary: │ Retaining 32 B in 1 objects
01-08 11:41:30.857 24515 25171 D LeakCanary: │ e instance of cerence.google.navigation.maps.sample.NavFragmentActivity with mDestroyed = true
01-08 11:41:30.857 24515 25171 D LeakCanary: │ ↓ d.e
01-08 11:41:30.857 24515 25171 D LeakCanary: │ ~
01-08 11:41:30.857 24515 25171 D LeakCanary: ╰→ cerence.google.navigation.maps.sample.NavFragmentActivity instance
01-08 11:41:30.857 24515 25171 D LeakCanary: ​ Leaking: YES (ObjectWatcher was watching this because cerence.google.navigation.maps.sample.NavFragmentActivity
01-08 11:41:30.857 24515 25171 D LeakCanary: ​ received Activity#onDestroy() callback and Activity#mDestroyed is true)
01-08 11:41:30.857 24515 25171 D LeakCanary: ​ Retaining 3.0 MB in 39053 objects
01-08 11:41:30.857 24515 25171 D LeakCanary: ​ key = 1949e352-b12f-4843-959f-761514098dad
01-08 11:41:30.857 24515 25171 D LeakCanary: ​ watchDurationMillis = 5166
01-08 11:41:30.857 24515 25171 D LeakCanary: ​ retainedDurationMillis = 165
01-08 11:41:30.857 24515 25171 D LeakCanary: ​ mApplication instance of cerence.google.navigation.maps.sample.MainApp
01-08 11:41:30.857 24515 25171 D LeakCanary: ​ mBase instance of androidx.appcompat.view.ContextThemeWrapper
01-08 11:41:30.857 24515 25171 D LeakCanary: ====================================
01-08 11:41:30.857 24515 25171 D LeakCanary: 0 LIBRARY LEAKS
01-08 11:41:30.858 24515 25171 D LeakCanary:
01-08 11:41:30.858 24515 25171 D LeakCanary: A Library Leak is a leak caused by a known bug in 3rd party code that you do not have control over.
01-08 11:41:30.858 24515 25171 D LeakCanary: See https://square.github.io/leakcanary/fundamentals-how-leakcanary-works/#4-categorizing-leaks
01-08 11:41:30.858 24515 25171 D LeakCanary: ====================================
01-08 11:41:30.858 24515 25171 D LeakCanary: 0 UNREACHABLE OBJECTS
01-08 11:41:30.858 24515 25171 D LeakCanary:
01-08 11:41:30.858 24515 25171 D LeakCanary: An unreachable object is still in memory but LeakCanary could not find a strong reference path
01-08 11:41:30.858 24515 25171 D LeakCanary: from GC roots.
01-08 11:41:30.858 24515 25171 D LeakCanary: ====================================
01-08 11:41:30.858 24515 25171 D LeakCanary: METADATA
01-08 11:41:30.858 24515 25171 D LeakCanary:
01-08 11:41:30.858 24515 25171 D LeakCanary: Please include this in bug reports and Stack Overflow questions.
01-08 11:41:30.858 24515 25171 D LeakCanary:
01-08 11:41:30.858 24515 25171 D LeakCanary: Build.VERSION.SDK_INT: 33
01-08 11:41:30.858 24515 25171 D LeakCanary: Build.MANUFACTURER: samsung
01-08 11:41:30.858 24515 25171 D LeakCanary: LeakCanary version: 2.14
01-08 11:41:30.858 24515 25171 D LeakCanary: App process name: cerence.google.navigation.maps.sample
01-08 11:41:30.858 24515 25171 D LeakCanary: Class count: 45316
01-08 11:41:30.858 24515 25171 D LeakCanary: Instance count: 466652
01-08 11:41:30.858 24515 25171 D LeakCanary: Primitive array count: 264560
01-08 11:41:30.858 24515 25171 D LeakCanary: Object array count: 72531
01-08 11:41:30.858 24515 25171 D LeakCanary: Thread count: 92
01-08 11:41:30.858 24515 25171 D LeakCanary: Heap total bytes: 60020255
01-08 11:41:30.858 24515 25171 D LeakCanary: Bitmap count: 173
01-08 11:41:30.858 24515 25171 D LeakCanary: Bitmap total bytes: 1679625
01-08 11:41:30.858 24515 25171 D LeakCanary: Large bitmap count: 0
01-08 11:41:30.858 24515 25171 D LeakCanary: Large bitmap total bytes: 0
01-08 11:41:30.858 24515 25171 D LeakCanary: Db 1: closed /data/user/0/cerence.google.navigation.maps.sample/databases/ue3.db
01-08 11:41:30.858 24515 25171 D LeakCanary: Db 2: open /data/user/0/cerence.google.navigation.maps.sample/databases/com.google.android.datatransport.events
01-08 11:41:30.858 24515 25171 D LeakCanary: Db 3: open /storage/emulated/0/Android/data/cerence.google.navigation.maps.sample/files/databases/refapp_db.db
01-08 11:41:30.858 24515 25171 D LeakCanary: Count of retained yet cleared: 3 KeyedWeakReference instances
01-08 11:41:30.858 24515 25171 D LeakCanary: Stats: LruCache[maxSize=3000,hits=150357,misses=420528,hitRate=26%]
01-08 11:41:30.858 24515 25171 D LeakCanary: RandomAccess[bytes=22919200,reads=420528,travel=239592751161,range=65887122,size=84370020]
01-08 11:41:30.858 24515 25171 D LeakCanary: Heap dump reason: 6 retained objects, app is not visible
01-08 11:41:30.858 24515 25171 D LeakCanary: Analysis duration: 31995 ms
01-08 11:41:30.858 24515 25171 D LeakCanary: Heap dump file path: /storage/emulated/0/Download/leakcanary-cerence.google.navigation.maps.
01-08 11:41:30.858 24515 25171 D LeakCanary: sample/2025-01-08_11-40-54_063.hprof
01-08 11:41:30.858 24515 25171 D LeakCanary: Heap dump timestamp: 1736354490843
01-08 11:41:30.858 24515 25171 D LeakCanary: Heap dump duration: 2170 ms
01-08 11:41:30.858 24515 25171 D LeakCanary: ====================================