Our game has been in development for several years. We use the Unity game engine version 2019.4 LTS. We are currently using Playfab sdk version 2.69.190625. Our PlayFabSharedSettings has always been set to use the "Unity Web Request". It is my understanding that this is the default mode and uses the main unity thread.
Recently due to a performance issue we changed this setting to use "Http Web Request". My understanding is that this handles the processing of the return values from the requests in a separate thread. Immediately we began to have stability issues and lockups in our game. Specifically when we would try to close the game, it would soft lock. We also saw crashes which contained a playfab call stack. When switching back to use the "Unity Web Request" mode, these issues stopped occurring.
A quick look at the playfab code shows calls such as:
PlayFabHttp.instance.OnPlayFabApiResult(reqContainer);
When looking at the CreateInstance() function inside SingletonMonoBehaviour, we see a bunch of non-threadsafe monobehavour calls such as FindObjectsOfType and AddComponent. It seems that during initialization or shutdown these calls could be made.
I would like to ask if this "Http Web Request" mode is indeed supported and if you recommend we use it. Are there any steps we must take in order to safely use it?
