Dropbox special files (.gdoc, .paper, .web, ...)

Is there a way to backup "special" files (.gdoc, .paper, .web, ...) from dropbox? Maybe with /2/files/export api?

I get a "failed to open source object: unsupported_file/.." error if one of these is in a dropbox repo.

Not at the moment.

Do these files export as something sensible?