Cannot save file to cryptomator vault

Hi, I have recently started using Cryptomator to encrypt my Dropbox files. However, I am unable to save a new R file to my cryptomator vault in rstudio. The save button is grayed out Screenshot%20from%202018-11-12%2009-06-01

I have set the permissions on my vault, and I can save new files there outside of Rstudio. I'm running Rstudio 1.1.456 on Ubuntu 18.04. Any ideas greatly appreciated.

EDIT: All works fine with RStudio 1.2.1091 (preview release https://www.rstudio.com/products/rstudio/download/preview/)