ef73de4 created the issue

When downloading gzip compressed files via cybderduck, they don't get automatically uncompressed.
It would be supercool if they did.

When storing files in Google Cloud, you can optionally store them compressed as gzip.
This can be done using gsutil with the -z or -Z flags.
There's no modification to the filename to signify this change...no ".gz" suffix.
Viewing the metadata of a file via Cyberduck I can see a few headers that could be used to identify and uncompress relevant files.
They have headers such as:
stored-content-encoding: gzip
Content-encoding: gzip

So if cyberduck sees these headers, it could potentially do an automatic decompression.

Potentially this could be expanded further to support compression on upload as well.