When I try build Android application. I got some error about R8. I used to be able to build successfully, but at some point I started getting errors.

Configure project :launcher WARNING: The option 'android.enableR8' is deprecated and should not be used anymore.

I googled android.enableR8 and it only worked for people developing apps in Android Studio.

My project currently uses PUN 2 to enable multiplayer, and Firebase for the database.

Also, the error continues below;

注意：D:\UnityProjects(ProjectName)\Temp\gradleOut\unityLibrary\src\main\java\com\unity3d\player\UnityPlayerActivity.javaは非推奨のAPIを使用またはオーバーライドしています。 注意:詳細は、-Xlint:deprecationオプションを指定して再コンパイルしてください。

It says UnityPlayerActivity.java uses a deprecated API, and check details by using -Xlint:deprecation option.

I don't know what -Xlint:deprecation is, and I don't remember changing the Unity Playern settings.

Is this a Unity bug? Or is it a bug in IL2CPP?