(Attached is a picture of the box I am referring to)
When I moused over Func<HttpContext> (seen in red as I had hit "skip" during load), the box seen in picture pops up, and it flickers in and out. It's not possible to actually click the "Locate Assembly" button because as soon as I move the mouse the popup disappears.
Attached is the project I used to create the DLL. It is a multi-target project. It uses .NET Core 3.0 Preview 6 and net46 targets. I was inspecting the .NET Core 3.0 version of the DLL.