bug: Android app can't load resources

Bug Report

Ionic version: 5.2.5

Current behavior: Build the app, and install the APK in the phone (Xiaomi Pocophone, Android 9). After this, when the app is opened, it just shows a blank screen. When inspected with Chrome DevTools/Remote Devices, it shows the following errors:

This ONLY happens in the Android build. In the web build that is used in ionic serve, it works perfectly.

Expected behavior: It should open the app as normal.

IMPORTANT: The app was working as expected in this phone, and also in an older, worse phone (although with some performance issues). But when I installed the Firebase FCM plugin, both the Ionic Native package and the Cordova plugin, also having put the google-services.json file in the platforms/android/app folder, it just started doing this behavior.

Steps to reproduce: Installing the Firebase FCM plugin, both Ionic package and Cordova plugin. Also, setting up the google-services.json file. That’s all the changes that led this app to stop working.

Ionic info:

Ionic:

   Ionic CLI                     : 5.2.5 (C:\Users\zerok\AppData\Roaming\npm\node_modules\ionic)
   Ionic Framework               : @ionic/angular 4.0.0
   @angular-devkit/build-angular : 0.12.4
   @angular-devkit/schematics    : 7.3.0
   @angular/cli                  : 7.1.0
   @ionic/angular-toolkit        : 1.3.0

Cordova:

   Cordova CLI       : 8.1.2 (cordova-lib@8.1.1)
   Cordova Platforms : android 7.1.4
   Cordova Plugins   : cordova-plugin-ionic-keyboard 2.1.3, cordova-plugin-ionic-webview 4.1.1, (and 14 other plugins)

Utility:

   cordova-res : 0.6.0
   native-run  : not installed

System:

   NodeJS : v11.8.0 (C:\Program Files\nodejs\node.exe)
   npm    : 6.5.0
   OS     : Windows 10

[Zerokk]

Hello @FernetB !

I was going to post an update on the topic just as you posted this. It does not seem to be the central issue, since now I managed to get it working doing the linked solution again.

[ionitron-bot[bot]]

Thanks for the issue! This issue is being locked to prevent comments that are not relevant to the original issue. If this is still an issue with the latest version of Ionic, please create a new issue and ensure the template is fully filled out.