Questions

We are observing an issue where our Android app freezes and triggers a system ANR (Input dispatching timed out / jdk.internal.misc.Unsafe.park).

Platform: Android (reproduced on multiple devices)

Symptom: The app hangs on a blank or splash screen during launch, leading to a system ANR.

Scope: While the issue is most noticeable on cold starts due to the longer delay before the WebView displays, our development team confirmed it can also occur while the application is actively running.

Build Verification: Reproduced across both our current release and prior builds, ruling out a recent build regression.

Below is the stack trace from our ANR log showing the parked main thread:

2026-09-04 14:40:11.061 [pid]-[tid] OneSignal com.example.mailapp W [OneSignal-ANR-Watchdog] OtelAnrDetector: ANR detected! Main thread unresponsive for 6002ms

2026-09-04 14:40:30.912 [system_pid]-[tid] ActivityManager [system] E ANR in com.example.mailapp
PID: [app_pid_1]
Reason: executing service com.example.mailapp/co.median.android.DownloadService
ErrorId: [redacted]
Frozen: false
Load: 1.46 / 0.99 / 0.66
----- Output from /proc/pressure/memory -----
some avg10=0.00 avg60=0.01 avg300=0.00 total=[redacted]
full avg10=0.00 avg60=0.00 avg300=0.00 total=[redacted]
----- End output from /proc/pressure/memory -----

CPU usage from 1ms to 5515ms later (2026-09-04 14:40:25.325 to 2026-09-04 14:40:30.840) with 99% awake:
18% [pid]/[third-party-app]: 5.7% user + 12% kernel / faults: 17722 minor 412 major
17% [pid]/system_server: 6.8% user + 10% kernel / faults: 8264 minor 555 major
12% [pid]/com.google.android.inputmethod.latin: 9% user + 3.4% kernel / faults: 5874 minor 1269 major
4.5% [pid]/com.android.systemui: 2.8% user + 1.6% kernel / faults: 6017 minor 253 major
3.2% [pid]/com.android.nfc: 1.8% user + 1.4% kernel / faults: 1692 minor 664 major
3.2% [pid]/com.example.mailapp: 1.8% user + 1.4% kernel / faults: 5276 minor 65 major
0% [pid]/media.swcodec: 0% user + 0% kernel / faults: 3318 minor 112 major
2.5% [pid]/adbd: 1% user + 1.4% kernel
0% [pid]/.qtidataservices: 0% user + 0% kernel / faults: 962 minor 691 major
2.5% [pid]/kworker/u16:0: 0% user + 2.5% kernel
2.1% [pid]/com.android.phone: 1.2% user + 0.9% kernel / faults: 754 minor 621 major
2.1% [pid]/kworker/u16:10: 0% user + 2.1% kernel
0% [pid]/com.google.SSRestartDetector: 0% user + 0% kernel / faults: 602 minor 765 major
0% [pid]/[vendor-secure-ui-service]: 0% user + 0% kernel / faults: 635 minor 828 major
0% [pid]/media.codec: 0% user + 0% kernel / faults: 1974 minor 66 major
1.8% [pid]/com.android.networkstack.process: 0.7% user + 1% kernel / faults: 558 minor 447 major
0% [pid]/[ims-service]: 0% user + 0% kernel / faults: 497 minor 758 major
0% [pid]/com.android.se: 0% user + 0% kernel / faults: 499 minor 686 major
1.6% [pid]/kswapd0: 0% user + 1.6% kernel
0% [pid]/.dataservices: 0% user + 0% kernel / faults: 496 minor 765 major
0% [pid]/[vendor-phone]: 0% user + 0% kernel / faults: 510 minor 798 major
0% [pid]/com.google.android.grilservice: 0% user + 0% kernel / faults: 414 minor 615 major
0% [pid]/com.android.ims.rcsservice: 0% user + 0% kernel / faults: 462 minor 691 major
0% [pid]/com.android.hbmsvmanager: 0% user + 0% kernel / faults: 494 minor 732 major
1.2% [pid]/logd: 0.3% user + 0.9% kernel / faults: 29 minor 2 major
0% [pid]/media.extractor: 0% user + 0% kernel / faults: 1602 minor 72 major
0% [pid]/kworker/u16:5: 0% user + 0% kernel
1.2% [pid]/kworker/u16:2: 0% user + 1.2% kernel
0.9% [pid]/irq/[redacted]: 0% user + 0.9% kernel
0% [pid]/tombstoned: 0% user + 0% kernel / faults: 15 minor 48 major
0.7% [pid]/kworker/u16:8: 0% user + 0.7% kernel
0.5% [pid]/logcat: 0.1% user + 0.3% kernel
0.5% [pid]/logcat: 0.3% user + 0.1% kernel
0.3% [pid]/rcu_preempt: 0% user + 0.3% kernel
0.3% [pid]/rcuop/4: 0% user + 0.3% kernel
0.3% [pid]/[vendor-wifi-service]: 0.1% user + 0.1% kernel / faults: 31 minor
0.3% [pid]/kworker/u17:1: 0% user + 0.3% kernel
0% [pid]/kworker/u17:2: 0% user + 0% kernel
0.3% [pid]/com.google.android.webview:sandboxed_process0: 0.1% user + 0.1% kernel / faults: 327 minor
0.1% [pid]/rcu_sched: 0% user + 0.1% kernel
0.1% [pid]/rcuop/0: 0% user + 0.1% kernel
0.1% [pid]/rcuop/2: 0% user + 0.1% kernel
0% [pid]/migration/4: 0% user + 0% kernel
0% [pid]/rcuos/4: 0% user + 0% kernel
0.1% [pid]/rcuop/6: 0% user + 0.1% kernel
0% [pid]/rcuos/6: 0% user + 0% kernel
0.1% [pid]/rcuop/7: 0% user + 0.1% kernel
0.1% [pid]/surfaceflinger: 0% user + 0.1% kernel / faults: 43 minor 8 major
0% [pid]/loop11: 0% user + 0% kernel
0% [pid]/loop13: 0% user + 0% kernel
0% [pid]/loop22: 0% user + 0% kernel
0.1% [pid]/netd: 0% user + 0.1% kernel / faults: 40 minor 14 major
2026-09-04 14:40:35.383 [pid]-[tid] FirebaseMessaging com.example.mailapp E Topic sync or token retrieval failed on hard failure exceptions: java.util.concurrent.ExecutionException: java.io.IOException: SERVICE_NOT_AVAILABLE. Won't retry the operation.

2026-09-04 14:46:14.872 [system_pid]-[tid] ActivityManager [system] E ANR in com.example.mailapp (com.example.mailapp/co.median.android.LaunchActivity)
PID: [app_pid_2]
Reason: Input dispatching timed out (Application does not have a focused window)
Parent: com.example.mailapp/co.median.android.LaunchActivity
ErrorId: [redacted]
Frozen: false
Load: 1.38 / 1.25 / 0.89
----- Output from /proc/pressure/memory -----
some avg10=0.09 avg60=0.47 avg300=0.21 total=[redacted]
full avg10=0.03 avg60=0.21 avg300=0.10 total=[redacted]
----- End output from /proc/pressure/memory -----

CPU usage from 0ms to 6279ms later (2026-09-04 14:46:08.539 to 2026-09-04 14:46:14.817):
18% [pid]/[third-party-app]: 12% user + 6.5% kernel / faults: 10967 minor 19 major
15% [pid]/[third-party-app]: 4.1% user + 10% kernel / faults: 17675 minor
14% [pid]/system_server: 5.1% user + 9.2% kernel / faults: 8059 minor 5 major
9.5% [pid]/com.google.android.inputmethod.latin: 7% user + 2.5% kernel / faults: 5269 minor 7 major
9.5% [pid]/[third-party-app]: 5.7% user + 3.8% kernel / faults: 3242 minor 4 major
6.3% [pid]/[third-party-app]: 4.7% user + 1.5% kernel / faults: 3703 minor 97 major
3.6% [pid]/com.android.systemui: 2% user + 1.5% kernel / faults: 6356 minor 4 major
3.1% [pid]/surfaceflinger: 1.5% user + 1.5% kernel / faults: 204 minor
3.1% [pid]/adbd: 1.4% user + 1.7% kernel / faults: 1 minor
2.8% [pid]/com.example.mailapp: 2% user + 0.7% kernel / faults: 5714 minor 1 major
2.7% [pid]/com.android.nfc: 1.7% user + 0.9% kernel / faults: 1601 minor 2 major
2.2% [pid]/media.swcodec: 1.1% user + 1.1% kernel / faults: 3308 minor
2% [pid]/kworker/u16:7: 0% user + 2% kernel
0.1% [pid]/.qtidataservices: 0% user + 0% kernel / faults: 824 minor
1.7% [pid]/kworker/u16:2: 0% user + 1.7% kernel
1.5% [pid]/com.android.phone: 1.2% user + 0.3% kernel / faults: 528 minor 3 major
1.5% [pid]/kworker/u16:9: 0% user + 1.5% kernel
1.4% [pid]/logd: 0.7% user + 0.6% kernel / faults: 79 minor
0.1% [pid]/media.codec: 0% user + 0% kernel / faults: 1966 minor 31 major
1.4% [pid]/com.android.networkstack.process: 1.1% user + 0.3% kernel / faults: 443 minor
0.1% [pid]/[vendor-secure-ui-service]: 0% user + 0% kernel / faults: 501 minor
1.4% [pid]/kworker/u16:6: 0% user + 1.4% kernel
0% [pid]/com.android.hbmsvmanager: 0% user + 0% kernel / faults: 376 minor
0% [pid]/[ims-service]: 0% user + 0% kernel / faults: 380 minor
0% [pid]/com.google.SSRestartDetector: 0% user + 0% kernel / faults: 479 minor
1.1% [pid]/media.extractor: 0.6% user + 0.4% kernel / faults: 1589 minor
0% [pid]/.dataservices: 0% user + 0% kernel / faults: 373 minor
0% [pid]/[vendor-phone]: 0% user + 0% kernel / faults: 378 minor
1.1% [pid]/com.google.android.grilservice: 0.9% user + 0.1% kernel / faults: 312 minor
0% [pid]/com.android.se: 0% user + 0% kernel / faults: 384 minor 2 major
0% [pid]/com.android.ims.rcsservice: 0% user + 0% kernel / faults: 360 minor 1 major
0.7% [pid]/kcompactd0: 0% user + 0.7% kernel
0.7% [pid]/irq/[redacted]: 0% user + 0.7% kernel
0.6% [pid]/[vendor-wifi-service]: 0.3% user + 0.3% kernel / faults: 76 minor
0.6% [pid]/logcat: 0.1% user + 0.4% kernel
0.4% [pid]/rcu_preempt: 0% user + 0.4% kernel
0.4% [pid]/logcat: 0.1% user + 0.3% kernel
0.4% [pid]/kworker/u17:5: 0% user + 0.4% kernel
0.3% [pid]/rcu_sched: 0% user + 0.3% kernel
0.3% [pid]/rcuop/4: 0% user + 0.3% kernel
0% [pid]/tombstoned: 0% user + 0% kernel
0.3% [pid]/[authenticator-app]: 0.1% user + 0.1% kernel / faults: 14 minor 2 major
0.3% [pid]/kworker/u17:3: 0% user + 0.3% kernel
0.1% [pid]/init: 0.1% user + 0% kernel
0.1% [pid]/rcuop/2: 0% user + 0.1% kernel
0% [pid]/rcuos/2: 0% user + 0% kernel
0.1% [pid]/ksoftirqd/3: 0% user + 0.1% kernel
0% [pid]/rcuos/4: 0% user + 0% kernel
0.1% [pid]/rcuop/5: 0% user + 0.1% kernel
0.1% [pid]/rcuop/6: 0% user + 0.1% kernel

Is this a known behavior with native WebView thread initialization or bridge event handling on Android, and is there a recommended configuration or framework fix to resolve it? Thank you.