I'm working on a project that has me using the Creative Cloud files to store the changes I make. I know I'm not using all of the features, but with my own personal account on two machines and my employers site license on the other, I end up using the browser version of Creative Cloud to upload and download files on my work computer.
When I download a book file (.indb), Creative Cloud and my browser seem to get confused as to what kind of file it is. Creative Cloud asks me and doesn't have an option for InDesign Book. When it downloads, it downloads as a .octet-stream file. I later go to Finder and change the extension to indb and life is good.