The konsole handbook contains the following phrase:

Any profiles which have Show in Menu checked will be listed by their name in the File → New Tab menu. There will be no submenu if only the default profile is to be shown.

I looked and looked and looked again, but I can't find any checkbox that says "Show In Menu." So I don't get to choose from profiles when I hit "New Tab"

Maybe I'm just missing it and someone can tell me where it is. I'll feel foolish, but at least I'll be straightened out.

I'm using Fedora 29 MATE/Compiz 64-bit. I thought I would add KDE but I haven't got there yet. My konsole version is Version 18.08.3. My computer is a couple of years old but it is pretty much standard issue.

Thanks for reading this far.

Looks like that's referring to the "Show" column in the profiles list. Click on the Show cell for a profile to toggle it.