On the Mac, .rftd is a format that’s available for ScratchPad notes. However, Scrivener for Windows does not recognize this format.
It seems that RFTD is not a format fully supported natively in Windows. However, can there be a workaround of sorts where Scrivener Windows accesses the .rtf file within that .rtfd folder?
Much of the time, I will be adding text to my ScratchPad docs, but because I am working on a grahpic novel of sorts, I may include images from time to time.
Unfortunately that wouldn’t be safe to do, as the RTFD format’s sub-file could be damaged by editing it directly in an RTF editor that wasn’t using the Mac to edit the file. For example if you drop an image into the text editor, it adds the image as a separate file, and then inserts an invisible marker at the location where the file would placed. Editing the RTF in another editor would most likely delete the marker, leaving the image without reference.
You’ll be best off using RTF on both platforms, and you shouldn’t run into any problems doing so. The only reason to use RTFD is if you really need to integrate with macOS text editors that cannot read RTF fully.
Ah, that’s too bad.
The only reason I do use the RTFD format is to enable the pasting of graphics from time to time. Using RTF format is ok most of the time.
What a bugger, with these cross-platform compatibility 
Oh, if that’s the main reason you’ve been using it, you can paste pictures into RTF as well, and it is cross-platform compatible with Scrivener for Windows!
Oh, I can paste pictures into RFT document? Interesting. I thought on the Mac side, it always forces me to convert to RTFD (at least when I’m using TextEdit to do that. I haven’t tried elsewhere).
Update:
You’re right! Yippee!!
I also tested this in TextEdit. When I create a new document, type some text and add a picture, it forces me to save either in WebArchive format or Rich Text Document with Attachments (which is Apple’s way of saying RTFD). Grr…! And also, looks like TextEdit does not properly display RTF documents that have pictures. It simply doesn’t show the picture. sigh That’s fine though. I hardly ever use TextEdit to open RTF documents, but still…
You are not wrong about TextEdit, and for that matter most Mac software that handles images in the text. NeXTSTEP came up with the RTFD format (and that OS eventually “became” Mac OS X) as a way of handling images. But since Scrivener has to make documents for more than just Mac users, we implemented the proper RTF image specification into it—and once you do that, you might as well support them wherever you can, not just in the editor. TextEdit won’t see them, nor will it see a number of other RTF features that Scrivener supports (like footnotes).
Thanks for the explanation! Boo on Apple for not having their software fully supporting a standard format.