Thanks!
I don't know if it's an OS upgrade or what, but in the past, there used to be a drop-down where you could select file types. It's gone. Instead there's an "Option" button in the lower left of Apple's file requestor. In the example below, I drew a red square around it.
Click on "Option" and it lets you pick the filetypes.
The "Option" button, instead of the filetypes dropdown must be new.