HttpContext.Current null in callbacks (caused by WithCurrentCulture)

[Bouke]

I'm using Asp.Net Identity on .Net Framework 4.8 and MVC 5. I'm using HttpContext to track contextual information about a request. However Asp.Net Identity uses ConfigureAwait(false), which means that HttpContext.Current becomes null in callbacks. For example when subclassing PortalSignInManager, HttpContext.Current is null inside SignInAsync.

I suppose WithCurrentCulture was introduced when Asp.Net Core didn't flow HttpContext. However that's no longer the case for newer versions, and this workaround is breaking my application.