Guard should support other file extensions in Drive
Guard -- given the appropriate key -- should be able to decrypt and preview files that were encrypted with GnuPG before being uploaded. These files have either the `.gpg` (binary) or `.asc` (text) extension.
The web interface has an option to "Add and encrypt local file" with Guard. Supporting the other file extensions associated with popular implementations of OpenPGP would enable a similar workflow involving WebDAV.
Renaming files to change their extensions -- from `asc` or `gpg` to `pgp` -- is an inconvenient workaround.