Installing the latest (2.155) SDK to Unity 2019 gives you syntax error.
Assets\PlayFabSDK\Shared\Internal\PlayFabHttp\PlayFabUnityHttp.cs(122,14): error CS1026: ) expected
Assets\PlayFabSDK\Shared\Internal\PlayFabHttp\PlayFabUnityHttp.cs(117,19): error CS1003: Syntax error, '(' expected
More details in this post: https://community.playfab.com/questions/64046/i-keep-getting-these-two-errors-in-my-console-and-1.html