I have a macbook running Mojave 10 which I haven't used very much yet. I have downloaded the desktop Dropbox app and Dropbox does appear in Finder. However, when I try to save a file - that was originally saved in Dropbox, it will only allow me to save to the hard disk or to cloud storage which only offers One Drive, One Drive for Business or Share Point. When I ask to add another cloud storage there is no option for Dropbox.
Additionally I have tried to set up smart sync. The process only allows me to get as far as the button to Open Preferences. On clicking this, nothing happens and I can go no further. I reinstalled the desktop app today so I know it is up-to-date.