[Bug] ANR with Notification

[jgerdoganakgun]

Description

In my Unity project, I am using the Firebase Unity SDK (Analytics, Crashlytics, App, Messaging, and Remote Config). I have observed an ANR reported in the Firebase Console.

Some of the crash reports show no logs, while others include a notification_received log entry together with the current threads.

Device state (from Firebase Crashlytics):
• Background: 92%
• Rooted: 0%
• Proximity sensor: 98%
• Free RAM: 0B

Expected Behavior:
The app should not hang or trigger an ANR when receiving a Firebase Cloud Messaging event or while in background.

Actual Behavior:
• ANR is reported in Firebase Console.
• Often no useful log is attached.
• Occasionally, only a notification_received log with thread information is attached.

Release Distribution Type: https://developers.google.com/unity/archive#firebase
Installation Method: UPM with custom repo that contains .tgz contents

Reproducing the issue

Couldn't reproduce, and I was not able to isolate a scenario with sample code.

Firebase Unity SDK Version

13.1.0

Unity editor version

6000.0.53f1

Installation Method

Unity Package Manager

Problematic Firebase Component(s)

Messaging

Other Firebase Component(s) in use

Remote Config

Additional SDKs you are using

Applovin 8.3.1

Targeted Platform(s)

Android

Unity editor platform

Mac

Scripting Runtime

IL2CPP

Release Distribution Type

Open-source from this repo

Relevant Log Output

Triggered ANR, Unknown root cause

          main (native):tid=1 systid=28774 
#00 pc 0x9ef58 libc.so (__epoll_pwait + 20) (BuildId: e5ac3826f29eccb686494090360db63b)
#01 pc 0x6ee05 libc.so (epoll_wait + 16) (BuildId: e5ac3826f29eccb686494090360db63b)
#02 pc 0x1049f libutils.so (android::Looper::pollInner + 126) (BuildId: 8b2beef89031d2927b32fb7b6e5da388)
#03 pc 0x103c7 libutils.so (android::Looper::pollOnce + 58) (BuildId: 8b2beef89031d2927b32fb7b6e5da388)
#04 pc 0xeedc7 libandroid_runtime.so (android::android_os_MessageQueue_nativePollOnce + 24) (BuildId: 7405dcfc37a07d689ac2b9e18cd73825)
       at android.os.MessageQueue.nativePollOnce(Native method)
       at android.os.MessageQueue.next(MessageQueue.java:335)
       at android.os.Looper.loopOnce(Looper.java:161)
       at android.os.Looper.loop(Looper.java:288)
       at android.app.ActivityThread.main(ActivityThread.java:8061)
       at java.lang.reflect.Method.invoke(Native method)
       at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:703)
       at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:911)

If using CocoaPods for Apple platforms, the project's Podfile.lock

Expand Podfile.lock snippet

👀 Replace this line with the contents of your Podfile.lock!

[google-oss-bot]

I couldn't figure out how to label this issue, so I've labeled it for a human to triage. Hang tight.

[niccolo-hare]

Hi @jgerdoganakgun, thanks for reaching out. I tried setting up a similar sample app, including the SDKs you indicated, but I didn't encounter any ANRs when receiving a message. I also tried sending different types of messages, but the SDK seems to handle them as expected. Though I did notice that a newer version of the Firebase SDK was released recently (currently v13.2.0). Could you try updating and see if that helps resolve the issue?

[jgerdoganakgun]

Thank you for your response. On the same day, I updated the Firebase SDK to version 13.2.0, and here are the results for that specific version:

Another stack trace

I understand that you were not able to reproduce the issue. We also couldn’t reproduce it, but based on this stack trace, our only remaining suspicion points to Firebase Messaging.