ANR Problem Webview - Firebase + Webview

Hello,

I am constantly having ANR issues reported by Google Play on their analytics platform.

In this case, initially we thought it was a Firebase problem since some people had similar problems for unity firebase, so they recommended us to upgrade to the latest version of firebase, which we have done but the errors persist.

After digging a bit in the logs we found this:

Error Name: Input dispatching timed out (10d93b0 app.kokorokids.app/com.google.firebase.MessagingUnityPlayerActivity (server) is not responding. Waited 10001ms for MotionEvent)

Error Log:
"main" prio=5 tid=1 Native
#00 pc 0000000000086b8c /apex/com.android.runtime/lib64/bionic/libc.so (syscall+28)
#00 pc 000000000008a938 /apex/com.android.runtime/lib64/bionic/libc.so (__futex_wait_ex(void volatile*, bool, int, bool, timespec const*)+144)
#00 pc 00000000000ec784 /apex/com.android.runtime/lib64/bionic/libc.so (NonPI::MutexLockWithTimeout(pthread_mutex_internal_t*, bool, timespec const*)+688)
#00 pc 000000000017baa4 /data/app/~~s4LgLhlHDTFDqusDf7SmRw==/app.kokorokids.app-IdOQIEkINTdhy7aUZe2vqA==/lib/arm64/libunity.so (???)
#00 pc 000000000017b958 /data/app/~~s4LgLhlHDTFDqusDf7SmRw==/app.kokorokids.app-IdOQIEkINTdhy7aUZe2vqA==/lib/arm64/libunity.so (UnitySendMessage+116)
#00 pc 000000000034069c /data/app/~~s4LgLhlHDTFDqusDf7SmRw==/app.kokorokids.app-IdOQIEkINTdhy7aUZe2vqA==/lib/arm64/libunity.so (???)
at com.unity3d.player.UnityPlayer.nativeUnitySendMessage (Native method)
at com.unity3d.player.UnityPlayer.UnitySendMessage (unavailable)
at net.gree.unitywebview.CWebViewPluginInterface$1.run (CWebViewPluginInterface.java:90)
at android.app.Activity.runOnUiThread (Activity.java:7154)
at net.gree.unitywebview.CWebViewPluginInterface.call (CWebViewPluginInterface.java:88)
at net.gree.unitywebview.CWebViewPlugin$2$2.onReceivedHttpError (CWebViewPlugin.java:295)
at Pz.a (chromium-TrichromeWebViewGoogle.aab-stable-475810133:6)
at A9.handleMessage (chromium-TrichromeWebViewGoogle.aab-stable-475810133:78)
at android.os.Handler.dispatchMessage (Handler.java:106)
at android.os.Looper.loop (Looper.java:246)
at android.app.ActivityThread.main (ActivityThread.java:8587)
at java.lang.reflect.Method.invoke (Native method)
at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run (RuntimeInit.java:602)
at com.android.internal.os.ZygoteInit.main (ZygoteInit.java:1130)

Start with the stack trace entries in CWebViewPluginInterface.java at lines 88-90 and CWebViewPlugin.java at line 295, focusing on the onReceivedHttpError path and its UI-thread dispatch. Trace how this path reaches UnitySendMessage, then reproduce or analyze the reported Android ANR; done means identifying a confirmed cause and documenting or implementing a verified fix.