com.bandainamcoent.imas_millionlive_theaterdays: Firebase Messaging component is not present

[Fighter19]

Affected app
Name: THE IDOLM@STER MILLION LIVE: THEATER DAYS
Package id: com.bandainamcoent.imas_millionlive_theaterdays

Describe the bug
Shortly after the game is launched it crashes.

Expected behavior
Game should proceed to launch

System
Android Version: 11
Custom ROM: /e/OS (20221202.011327)

microG
microG Core version: 0.2.25.223616-9 (13f943e)-noen
microG Self-Check results: All ticked

Additional context

Most likely important part of logcat:

12-28 20:19:54.078 12418 14894 F ive_theaterday: runtime.cc:655] Pending exception java.lang.NullPointerException: Firebase Messaging component is not present
12-28 20:19:54.078 12418 14894 F ive_theaterday: runtime.cc:655]   at java.lang.Object com.google.android.gms.common.internal.Preconditions.checkNotNull(java.lang.Object, java.lang.Object) (com.google.android.gms:play-services-basement@@17.6.0:2)
12-28 20:19:54.078 12418 14894 F ive_theaterday: runtime.cc:655]   at com.google.firebase.messaging.FirebaseMessaging com.google.firebase.messaging.FirebaseMessaging.getInstance(com.google.firebase.FirebaseApp) (com.google.firebase:firebase-messaging@@23.0.0:3)
12-28 20:19:54.078 12418 14894 F ive_theaterday: runtime.cc:655]   at com.google.firebase.messaging.FirebaseMessaging com.google.firebase.messaging.FirebaseMessaging.getInstance() (com.google.firebase:firebase-messaging@@23.0.0:1)
12-28 20:19:54.078 12418 14894 F ive_theaterday: runtime.cc:655]   at boolean com.unity3d.player.UnityPlayer.nativeRender() ((null):-2)
12-28 20:19:54.078 12418 14894 F ive_theaterday: runtime.cc:655]   at boolean com.unity3d.player.UnityPlayer.access$300(com.unity3d.player.UnityPlayer) ((null):-1)
12-28 20:19:54.078 12418 14894 F ive_theaterday: runtime.cc:655]   at boolean com.unity3d.player.UnityPlayer$e$1.handleMessage(android.os.Message) ((null):-1)
12-28 20:19:54.078 12418 14894 F ive_theaterday: runtime.cc:655]   at void android.os.Handler.dispatchMessage(android.os.Message) (Handler.java:102)
12-28 20:19:54.080 12418 14894 F ive_theaterday: runtime.cc:655]   at void android.os.Looper.loop() (Looper.java:223)
12-28 20:19:54.080 12418 14894 F ive_theaterday: runtime.cc:655]   at void com.unity3d.player.UnityPlayer$e.run() ((null):-1)

tombstone_01.txt

[Fighter19]

Maybe related to #313 ?
EDIT:
Related line in Firebase SDK is here:
https://github.com/firebase/firebase-android-sdk/blob/e461cb73684db0255e5e6ef4ed8f4ca98fd285c1/firebase-messaging/src/main/java/com/google/firebase/messaging/FirebaseMessaging.java#L158
EDIT2: I was unable to reproduce it using the messaging testapp from https://github.com/firebase/quickstart-cpp. I linked it towards the prebuilt C++ SDK version 8.8.0 but it seemed to work correctly.
Sounds like some specific incompatibility with the Unity version of it.

[Fighter19]

Upon further inspection, this problem seems unrelated to microg, as it also occurs with Google's GSMCore on the same system image.
EDIT (for any one who might want to investigate as well):
During the investigation, I came to the conclusion that it had to be related to the ROM I was using (/e/os).
Apparently, some modifications to the way the applications are loaded are causing the components not to be registered.
I suspect this has to do with signature spoofing. Maybe the AndroidManifest file gets altered after first load, maybe it's the integrated Anti-Cheat software, interfering with it by reimplementing certain functions?
On a "normal" LineageOS ROM, this issue does not occur.