Normally, I can use the rectangular, press Ctrl-C, Ctrl -N, Ctrl V - and then I have a copy. But tha

Could you please post screenshots with the pertinent Panels (Toolbar, Layers, Options Bar, …) visible? 

Does the active Layer actually have pixel content in the selected area? 

Hey, @graverholt. Welcome to the Photoshop Community. I'll need more info to help you figure this out. Please share the system info from Photoshop Help > System info > Copy & paste into a text document > upload & attach here. 

I tried to recreate this based on the description in the latest version of Photoshop. 

CTRL + C to copy a layer/selection. 

CTRL + N to launch File > New window 
Clipboard preset is selected > Click Create > Opens new document. 
Ctrl + V to paste. 

Do you notice a difference? Please share more details.

Thanks!

Sameer K