Permissions on application startup

Why doesn’t Unity ask for Android permissions on application startup after version 2018.3? Is it possible to have Unity ask for permissions on application startup?

Just ask for permission through scripting.

void Start ()
    {
        #if PLATFORM_ANDROID
        if (!Permission.HasUserAuthorizedPermission(Permission.Microphone))
        {
            Permission.RequestUserPermission(Permission.Microphone);
            dialog = new GameObject();
            }
        #endif
    }

More documentation on this can be found in Unitys manuals.