How to allow Java applications (Umlet) to access OneDrive files on Mac?

I'm fond of this little program: https://www.umlet.com/ . Never had issue with running it on Windows. Recently at work I have to use it on a Mac, and if I try to save/open a diagram in a OneDrive folder synced by Microsoft OneDrive sync client, the open/save dialog does not show any files in the OneDrive folder. I suspect this has something to do with granting permissions to access OneDrive files, but I can't find any options anywhere to allow this. Any solution?