Following is the similar question as below but it was asked 9 years ago so wanted to know if there is any solution yet which supports all browser. In my case everything works fine on Chrome and Edge but on Firefox HttpContext is empty.
Using 4.0 SignalR with ASP.NET MVC and Jquery SignalR plugin 1.2.2
Why is HTTPContext.Current.Session null using SignalR 2.x libraries in a ASP .Net MVC application?