com.google.protobuf.AbstractProtobufList.ensureIsMutable (AbstractProtobufList.java:161)

[gkaffka]

[REQUIRED] Step 2: Describe your environment

• Android Studio version: Android Studio Quail 2 | 2026.1.2
• Firebase Component: Firebase performance
• Component version: Firebase BOM: 34.14.0

[REQUIRED] Step 3: Describe the problem

Steps to reproduce:

Stack trace from firebase Crashlytics:

• Crash: UnsupportedOperationException at AbstractProtobufList.ensureIsMutable via NetworkRequestMetricBuilder.build() → NetworkRequestMetric$Builder.addAllPerfSessions
• Trigger: InstrHttpsURLConnection.disconnect() called from a ConnectivityManager.NetworkCallback.onLost on ConnectivityThread (Braze SDK disconnecting its in-flight request on network loss), racing the request thread's own build() — i.e., NetworkRequestMetricBuilder is not thread-safe and build() runs twice
• Repro context: app in background, device loses connectivity mid-request; observed on Android 13–16, Crashlytics SDK 20.0.6

Fatal Exception: java.lang.UnsupportedOperationException:
       at com.google.protobuf.AbstractProtobufList.ensureIsMutable(AbstractProtobufList.java:161)
       at com.google.protobuf.ProtobufArrayList.add(ProtobufArrayList.java:52)
       at com.google.protobuf.AbstractMessageLite$Builder.addAllCheckingNulls(AbstractMessageLite.java:361)
       at com.google.protobuf.AbstractMessageLite$Builder.addAll(AbstractMessageLite.java:414)
       at com.google.protobuf.AbstractMessageLite.addAll(AbstractMessageLite.java:123)
       at com.google.firebase.perf.v1.NetworkRequestMetric.addAllPerfSessions(NetworkRequestMetric.java:1232)
       at com.google.firebase.perf.v1.NetworkRequestMetric.access$2900(NetworkRequestMetric.java:17)
       at com.google.firebase.perf.v1.NetworkRequestMetric$Builder.addAllPerfSessions(NetworkRequestMetric.java:2355)
       at com.google.firebase.perf.metrics.NetworkRequestMetricBuilder.build(NetworkRequestMetricBuilder.java:318)
       at com.google.firebase.perf.network.InstrURLConnectionBase.disconnect(InstrURLConnectionBase.java:80)
       at com.google.firebase.perf.network.InstrHttpsURLConnection.disconnect(InstrHttpsURLConnection.java:63)
       at bo.app.i7.a(SourceFile:3)
       at bo.app.i7.c(SourceFile:3)
       at bo.app.f7.g(SourceFile:2)
       at bo.app.y6.a(SourceFile:130)
       at bo.app.y6.a(SourceFile:35)
       at bo.app.m8.b(SourceFile:62)
       at bo.app.c5.a(SourceFile:29)
       at bo.app.y4.onLost(SourceFile:8)
       at android.net.ConnectivityManager$CallbackHandler.handleMessage(ConnectivityManager.java:4688)
       at android.os.Handler.dispatchMessage(Handler.java:132)
       at android.os.Looper.dispatchMessage(Looper.java:358)
       at android.os.Looper.loopOnce(Looper.java:288)
       at android.os.Looper.loop(Looper.java:392)
       at android.os.HandlerThread.run(HandlerThread.java:139)

Firebase Background Thread #1:
       at dalvik.system.VMStack.getThreadStackTrace(VMStack.java)
       at java.lang.Thread.getStackTrace(Thread.java:2852)
       at java.lang.Thread.getAllStackTraces(Thread.java:2919)
       at com.google.firebase.crashlytics.internal.common.CrashlyticsReportDataCapture.populateThreadsList(CrashlyticsReportDataCapture.java:343)
       at com.google.firebase.crashlytics.internal.common.CrashlyticsReportDataCapture.populateExecutionData(CrashlyticsReportDataCapture.java:314)
       at com.google.firebase.crashlytics.internal.common.CrashlyticsReportDataCapture.populateEventApplicationData(CrashlyticsReportDataCapture.java:261)
       at com.google.firebase.crashlytics.internal.common.CrashlyticsReportDataCapture.captureEventData(CrashlyticsReportDataCapture.java:112)
       at com.google.firebase.crashlytics.internal.common.SessionReportingCoordinator.persistEvent(SessionReportingCoordinator.java:337)
       at com.google.firebase.crashlytics.internal.common.SessionReportingCoordinator.persistFatalEvent(SessionReportingCoordinator.java:130)
       at com.google.firebase.crashlytics.internal.common.CrashlyticsController$2.call(CrashlyticsController.java:219)
       at com.google.firebase.crashlytics.internal.common.CrashlyticsController$2.call(CrashlyticsController.java:205)
       at com.google.firebase.crashlytics.internal.concurrency.CrashlyticsWorker.lambda$submitTask$2(CrashlyticsWorker.java:118)
       at com.google.android.gms.tasks.zze.run(zze.java:1)
       at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1100)
       at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
       at com.google.firebase.concurrent.CustomThreadFactory.lambda$newThread$0(CustomThreadFactory.java:47)
       at java.lang.Thread.run(Thread.java:1572)

kotlinx.coroutines.DefaultExecutor:
       at jdk.internal.misc.Unsafe.park(Unsafe.java)
       at java.util.concurrent.locks.LockSupport.parkNanos(LockSupport.java:276)
       at kotlinx.coroutines.DefaultExecutor.run(DefaultExecutor.kt:118)
       at java.lang.Thread.run(Thread.java:1572)

ProcessStablePhenotypeFlag:
       at jdk.internal.misc.Unsafe.park(Unsafe.java)
       at java.util.concurrent.locks.LockSupport.park(LockSupport.java:376)
       at java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionNode.block(AbstractQueuedSynchronizer.java:520)
       at java.util.concurrent.ForkJoinPool.unmanagedBlock(ForkJoinPool.java:3797)
       at java.util.concurrent.ForkJoinPool.managedBlock(ForkJoinPool.java:3738)
       at java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject.await(AbstractQueuedSynchronizer.java:1752)
       at java.util.concurrent.ScheduledThreadPoolExecutor$DelayedWorkQueue.take(ScheduledThreadPoolExecutor.java:1170)
       at java.util.concurrent.ScheduledThreadPoolExecutor$DelayedWorkQueue.take(ScheduledThreadPoolExecutor.java:899)
       at java.util.concurrent.ThreadPoolExecutor.getTask(ThreadPoolExecutor.java:1026)
       at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1086)
       at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
       at java.lang.Thread.run(Thread.java:1572)

ConscryptStatsLogWriter:
       at jdk.internal.misc.Unsafe.park(Unsafe.java)
       at java.util.concurrent.locks.LockSupport.park(LockSupport.java:376)
       at java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionNode.block(AbstractQueuedSynchronizer.java:520)
       at java.util.concurrent.ForkJoinPool.unmanagedBlock(ForkJoinPool.java:3797)
       at java.util.concurrent.ForkJoinPool.managedBlock(ForkJoinPool.java:3738)
       at java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject.await(AbstractQueuedSynchronizer.java:1752)
       at java.util.concurrent.LinkedBlockingQueue.take(LinkedBlockingQueue.java:435)
       at java.util.concurrent.ThreadPoolExecutor.getTask(ThreadPoolExecutor.java:1026)
       at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1086)
       at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
       at java.lang.Thread.run(Thread.java:1572)

DefaultDispatcher-worker-17:
       at jdk.internal.misc.Unsafe.park(Unsafe.java)
       at java.util.concurrent.locks.LockSupport.parkNanos(LockSupport.java:417)
       at kotlinx.coroutines.scheduling.CoroutineScheduler$Worker.park(CoroutineScheduler.kt:833)
       at kotlinx.coroutines.scheduling.CoroutineScheduler$Worker.tryPark(CoroutineScheduler.kt:781)
       at kotlinx.coroutines.scheduling.CoroutineScheduler$Worker.runWorker(CoroutineScheduler.kt:751)
       at kotlinx.coroutines.scheduling.CoroutineScheduler$Worker.run(CoroutineScheduler.kt:704)

Firebase-Messaging-Init:
       at jdk.internal.misc.Unsafe.park(Unsafe.java)
       at java.util.concurrent.locks.LockSupport.park(LockSupport.java:376)
       at java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionNode.block(AbstractQueuedSynchronizer.java:520)
       at java.util.concurrent.ForkJoinPool.unmanagedBlock(ForkJoinPool.java:3797)
       at java.util.concurrent.ForkJoinPool.managedBlock(ForkJoinPool.java:3738)
       at java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject.await(AbstractQueuedSynchronizer.java:1752)
       at java.util.concurrent.ScheduledThreadPoolExecutor$DelayedWorkQueue.take(ScheduledThreadPoolExecutor.java:1170)
       at java.util.concurrent.ScheduledThreadPoolExecutor$DelayedWorkQueue.take(ScheduledThreadPoolExecutor.java:899)
       at java.util.concurrent.ThreadPoolExecutor.getTask(ThreadPoolExecutor.java:1026)
       at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1086)
       at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
       at com.google.android.gms.common.util.concurrent.zza.run(zza.java:2)
       at java.lang.Thread.run(Thread.java:1572)

pool-18-thread-1:
       at jdk.internal.misc.Unsafe.park(Unsafe.java)
       at java.util.concurrent.locks.LockSupport.park(LockSupport.java:376)
       at java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionNode.block(AbstractQueuedSynchronizer.java:520)
       at java.util.concurrent.ForkJoinPool.unmanagedBlock(ForkJoinPool.java:3797)
       at java.util.concurrent.ForkJoinPool.managedBlock(ForkJoinPool.java:3738)
       at java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject.await(AbstractQueuedSynchronizer.java:1752)
       at java.util.concurrent.LinkedBlockingQueue.take(LinkedBlockingQueue.java:435)
       at java.util.concurrent.ThreadPoolExecutor.getTask(ThreadPoolExecutor.java:1026)
       at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1086)
       at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
       at java.lang.Thread.run(Thread.java:1572)

queue-1-2:
       at jdk.internal.misc.Unsafe.park(Unsafe.java)
       at java.util.concurrent.locks.LockSupport.park(LockSupport.java:376)
       at java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionNode.block(AbstractQueuedSynchronizer.java:520)
       at java.util.concurrent.ForkJoinPool.unmanagedBlock(ForkJoinPool.java:3797)
       at java.util.concurrent.ForkJoinPool.managedBlock(ForkJoinPool.java:3738)
       at java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject.await(AbstractQueuedSynchronizer.java:1752)
       at java.util.concurrent.LinkedBlockingQueue.take(LinkedBlockingQueue.java:435)
       at java.util.concurrent.ThreadPoolExecutor.getTask(ThreadPoolExecutor.java:1026)
       at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1086)
       at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
       at java.lang.Thread.run(Thread.java:1572)

pool-29-thread-1:
       at jdk.internal.misc.Unsafe.park(Unsafe.java)
       at java.util.concurrent.locks.LockSupport.park(LockSupport.java:376)
       at java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionNode.block(AbstractQueuedSynchronizer.java:520)
       at java.util.concurrent.ForkJoinPool.unmanagedBlock(ForkJoinPool.java:3797)
       at java.util.concurrent.ForkJoinPool.managedBlock(ForkJoinPool.java:3738)
       at java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject.await(AbstractQueuedSynchronizer.java:1752)
       at java.util.concurrent.ScheduledThreadPoolExecutor$DelayedWorkQueue.take(ScheduledThreadPoolExecutor.java:1170)
       at java.util.concurrent.ScheduledThreadPoolExecutor$DelayedWorkQueue.take(ScheduledThreadPoolExecutor.java:899)
       at java.util.concurrent.ThreadPoolExecutor.getTask(ThreadPoolExecutor.java:1026)
       at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1086)
       at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
       at java.lang.Thread.run(Thread.java:1572)

RxComputationThreadPool-2:
       at jdk.internal.misc.Unsafe.park(Unsafe.java)
       at java.util.concurrent.locks.LockSupport.park(LockSupport.java:376)
       at java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionNode.block(AbstractQueuedSynchronizer.java:520)
       at java.util.concurrent.ForkJoinPool.unmanagedBlock(ForkJoinPool.java:3797)
       at java.util.concurrent.ForkJoinPool.managedBlock(ForkJoinPool.java:3738)
       at java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject.await(AbstractQueuedSynchronizer.java:1752)
       at java.util.concurrent.ScheduledThreadPoolExecutor$DelayedWorkQueue.take(ScheduledThreadPoolExecutor.java:1170)
       at java.util.concurrent.ScheduledThreadPoolExecutor$DelayedWorkQueue.take(ScheduledThreadPoolExecutor.java:899)
       at java.util.concurrent.ThreadPoolExecutor.getTask(ThreadPoolExecutor.java:1026)
       at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1086)
       at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
       at java.lang.Thread.run(Thread.java:1572)
       at okio.AsyncTimeout$Watchdog.run(AsyncTimeout.kt:5)

ConscryptStatsLogWriter:
       at jdk.internal.misc.Unsafe.park(Unsafe.java)
       at java.util.concurrent.locks.LockSupport.park(LockSupport.java:376)
       at java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionNode.block(AbstractQueuedSynchronizer.java:520)
       at java.util.concurrent.ForkJoinPool.unmanagedBlock(ForkJoinPool.java:3797)
       at java.util.concurrent.ForkJoinPool.managedBlock(ForkJoinPool.java:3738)
       at java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject.await(AbstractQueuedSynchronizer.java:1752)
       at java.util.concurrent.LinkedBlockingQueue.take(LinkedBlockingQueue.java:435)
       at java.util.concurrent.ThreadPoolExecutor.getTask(ThreadPoolExecutor.java:1026)
       at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1086)
       at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
       at java.lang.Thread.run(Thread.java:1572)

Firebase Scheduler Thread #0:
       at jdk.internal.misc.Unsafe.park(Unsafe.java)
       at java.util.concurrent.locks.LockSupport.park(LockSupport.java:376)
       at java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionNode.block(AbstractQueuedSynchronizer.java:520)
       at java.util.concurrent.ForkJoinPool.unmanagedBlock(ForkJoinPool.java:3797)
       at java.util.concurrent.ForkJoinPool.managedBlock(ForkJoinPool.java:3738)
       at java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject.await(AbstractQueuedSynchronizer.java:1752)
       at java.util.concurrent.ScheduledThreadPoolExecutor$DelayedWorkQueue.take(ScheduledThreadPoolExecutor.java:1170)
       at java.util.concurrent.ScheduledThreadPoolExecutor$DelayedWorkQueue.take(ScheduledThreadPoolExecutor.java:899)
       at java.util.concurrent.ThreadPoolExecutor.getTask(ThreadPoolExecutor.java:1026)
       at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1086)
       at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
       at com.google.firebase.concurrent.CustomThreadFactory.lambda$newThread$0(CustomThreadFactory.java:47)
       at java.lang.Thread.run(Thread.java:1572)

DefaultDispatcher-worker-11:
       at jdk.internal.misc.Unsafe.park(Unsafe.java)
       at java.util.concurrent.locks.LockSupport.parkNanos(LockSupport.java:417)
       at kotlinx.coroutines.scheduling.CoroutineScheduler$Worker.park(CoroutineScheduler.kt:833)
       at kotlinx.coroutines.scheduling.CoroutineScheduler$Worker.tryPark(CoroutineScheduler.kt:781)
       at kotlinx.coroutines.scheduling.CoroutineScheduler$Worker.runWorker(CoroutineScheduler.kt:751)
       at kotlinx.coroutines.scheduling.CoroutineScheduler$Worker.run(CoroutineScheduler.kt:704)

pool-31-thread-1:
       at jdk.internal.misc.Unsafe.park(Unsafe.java)
       at java.util.concurrent.locks.LockSupport.park(LockSupport.java:376)
       at java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionNode.block(AbstractQueuedSynchronizer.java:520)
       at java.util.concurrent.ForkJoinPool.unmanagedBlock(ForkJoinPool.java:3797)
       at java.util.concurrent.ForkJoinPool.managedBlock(ForkJoinPool.java:3738)
       at java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject.await(AbstractQueuedSynchronizer.java:1752)
       at java.util.concurrent.LinkedBlockingQueue.take(LinkedBlockingQueue.java:435)
       at java.util.concurrent.ThreadPoolExecutor.getTask(ThreadPoolExecutor.java:1026)
       at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1086)
       at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
       at java.lang.Thread.run(Thread.java:1572)

WM.task-4:
       at jdk.internal.misc.Unsafe.park(Unsafe.java)
       at java.util.concurrent.locks.LockSupport.park(LockSupport.java:376)
       at java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionNode.block(AbstractQueuedSynchronizer.java:520)
       at java.util.concurrent.ForkJoinPool.unmanagedBlock(ForkJoinPool.java:3797)
       at java.util.concurrent.ForkJoinPool.managedBlock(ForkJoinPool.java:3738)
       at java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject.await(AbstractQueuedSynchronizer.java:1752)
       at java.util.concurrent.LinkedBlockingQueue.take(LinkedBlockingQueue.java:435)
       at java.util.concurrent.ThreadPoolExecutor.getTask(ThreadPoolExecutor.java:1026)
       at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1086)
       at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
       at java.lang.Thread.run(Thread.java:1572)

FrameMetricsAggregator:
       at android.os.MessageQueue.nativePollOnce(MessageQueue.java)
       at android.os.MessageQueue.nextLegacy(MessageQueue.java:985)
       at android.os.MessageQueue.next(MessageQueue.java:1094)
       at android.os.Looper.loopOnce(Looper.java:222)
       at android.os.Looper.loop(Looper.java:392)
       at android.os.HandlerThread.run(HandlerThread.java:139)

Timer-0:
       at java.lang.Object.wait(Object.java)
       at java.lang.Object.wait(Object.java:405)
       at java.lang.Object.wait(Object.java:543)
       at java.util.TimerThread.mainLoop(Timer.java:562)
       at java.util.TimerThread.run(Timer.java:540)

RxCachedThreadScheduler-54:
       at jdk.internal.misc.Unsafe.park(Unsafe.java)
       at java.util.concurrent.locks.LockSupport.park(LockSupport.java:376)
       at java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionNode.block(AbstractQueuedSynchronizer.java:520)
       at java.util.concurrent.ForkJoinPool.unmanagedBlock(ForkJoinPool.java:3797)
       at java.util.concurrent.ForkJoinPool.managedBlock(ForkJoinPool.java:3738)
       at java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject.await(AbstractQueuedSynchronizer.java:1752)
       at java.util.concurrent.ScheduledThreadPoolExecutor$DelayedWorkQueue.take(ScheduledThreadPoolExecutor.java:1170)
       at java.util.concurrent.ScheduledThreadPoolExecutor$DelayedWorkQueue.take(ScheduledThreadPoolExecutor.java:899)
       at java.util.concurrent.ThreadPoolExecutor.getTask(ThreadPoolExecutor.java:1026)
       at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1086)
       at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
       at java.lang.Thread.run(Thread.java:1572)

Firebase Background Thread #2:
       at jdk.internal.misc.Unsafe.park(Unsafe.java)
       at java.util.concurrent.locks.LockSupport.park(LockSupport.java:376)
       at java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionNode.block(AbstractQueuedSynchronizer.java:520)
       at java.util.concurrent.ForkJoinPool.unmanagedBlock(ForkJoinPool.java:3797)
       at java.util.concurrent.ForkJoinPool.managedBlock(ForkJoinPool.java:3738)
       at java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject.await(AbstractQueuedSynchronizer.java:1752)
       at java.util.concurrent.LinkedBlockingQueue.take(LinkedBlockingQueue.java:435)
       at java.util.concurrent.ThreadPoolExecutor.getTask(ThreadPoolExecutor.java:1026)
       at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1086)
       at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
       at com.google.firebase.concurrent.CustomThreadFactory.lambda$newThread$0(CustomThreadFactory.java:47)
       at java.lang.Thread.run(Thread.java:1572)

RxComputationThreadPool-5:
       at jdk.internal.misc.Unsafe.park(Unsafe.java)
       at java.util.concurrent.locks.LockSupport.park(LockSupport.java:376)
       at java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionNode.block(AbstractQueuedSynchronizer.java:520)
       at java.util.concurrent.ForkJoinPool.unmanagedBlock(ForkJoinPool.java:3797)
       at java.util.concurrent.ForkJoinPool.managedBlock(ForkJoinPool.java:3738)
       at java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject.await(AbstractQueuedSynchronizer.java:1752)
       at java.util.concurrent.ScheduledThreadPoolExecutor$DelayedWorkQueue.take(ScheduledThreadPoolExecutor.java:1170)
       at java.util.concurrent.ScheduledThreadPoolExecutor$DelayedWorkQueue.take(ScheduledThreadPoolExecutor.java:899)
       at java.util.concurrent.ThreadPoolExecutor.getTask(ThreadPoolExecutor.java:1026)
       at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1086)
       at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
       at java.lang.Thread.run(Thread.java:1572)
       at okio.AsyncTimeout$Watchdog.run(AsyncTimeout.kt:5)

RxComputationThreadPool-7:
       at jdk.internal.misc.Unsafe.park(Unsafe.java)
       at java.util.concurrent.locks.LockSupport.park(LockSupport.java:376)
       at java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionNode.block(AbstractQueuedSynchronizer.java:520)
       at java.util.concurrent.ForkJoinPool.unmanagedBlock(ForkJoinPool.java:3797)
       at java.util.concurrent.ForkJoinPool.managedBlock(ForkJoinPool.java:3738)
       at java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject.await(AbstractQueuedSynchronizer.java:1752)
       at java.util.concurrent.ScheduledThreadPoolExecutor$DelayedWorkQueue.take(ScheduledThreadPoolExecutor.java:1170)
       at java.util.concurrent.ScheduledThreadPoolExecutor$DelayedWorkQueue.take(ScheduledThreadPoolExecutor.java:899)
       at java.util.concurrent.ThreadPoolExecutor.getTask(ThreadPoolExecutor.java:1026)
       at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1086)
       at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
       at java.lang.Thread.run(Thread.java:1572)
       at okio.AsyncTimeout$Watchdog.run(AsyncTimeout.kt:5)

DefaultDispatcher-worker-7:
       at jdk.internal.misc.Unsafe.park(Unsafe.java)
       at java.util.concurrent.locks.LockSupport.parkNanos(LockSupport.java:417)
       at kotlinx.coroutines.scheduling.CoroutineScheduler$Worker.park(CoroutineScheduler.kt:833)
       at kotlinx.coroutines.scheduling.CoroutineScheduler$Worker.tryPark(CoroutineScheduler.kt:781)
       at kotlinx.coroutines.scheduling.CoroutineScheduler$Worker.runWorker(CoroutineScheduler.kt:751)
       at kotlinx.coroutines.scheduling.CoroutineScheduler$Worker.run(CoroutineScheduler.kt:704)

Firebase Blocking Thread #195:
       at jdk.internal.misc.Unsafe.park(Unsafe.java)
       at java.util.concurrent.locks.LockSupport.parkNanos(LockSupport.java:417)
       at java.util.concurrent.LinkedTransferQueue$DualNode.await(LinkedTransferQueue.java:452)
       at java.util.concurrent.SynchronousQueue$Transferer.xferLifo(SynchronousQueue.java:194)
       at java.util.concurrent.SynchronousQueue.xfer(SynchronousQueue.java:235)
       at java.util.concurrent.SynchronousQueue.poll(SynchronousQueue.java:338)
       at java.util.concurrent.ThreadPoolExecutor.getTask(ThreadPoolExecutor.java:1025)
       at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1086)
       at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
       at com.google.firebase.concurrent.CustomThreadFactory.lambda$newThread$0(CustomThreadFactory.java:47)
       at java.lang.Thread.run(Thread.java:1572)

Seems to be the same issue reported on #6625

[lehcar09]

Hi @gkaffka, thank you for reaching out. It looks to me that this issue is similar to #6625, as you mentioned. Per our engineers, this was a confirmed bug in NetworkRequestMetricBuilder with a race condition.

By any chance were you able replicate the issue? Aside from that, can you share how many events per week you're getting for this crash?

[gkaffka]

@lehcar09 We could not replicate the issue directly, regarding the number of crashes per week, according to Firebase: This issue has 348 crash events affecting 344 users in the last 7 days.

[lehcar09]

Thanks for the details @gkaffka. I'll raise this to engineers and see what we can do here.