When upgrading the Android Gradle Plugin from version 8.6 to version 8.7, there was a noticeable APK size increase. Upon further investigation, I realised that this was caused by the fact that our custom build type that was being initialised with the release build type's configuration no longer had resource shrinking enabled, so unused resources were kept in the APK. This is due to a change in behaviour in AGP.

build.gradle.kts snippet:

android {
    buildTypes {
        val release by getting {
            isShrinkResources = true
            isMinifyEnabled = true
        }
        val official by creating {
            initWith(getByName("release"))
        }
    }
}

By adding isShrinkResources = true to the official build type, the APK size would get back to the expected value.

If this is intended behaviour, it should be documented somewhere. Otherwise, the behaviour should be reverted to the one in prior versions.