I have an iPhone 5s running iOS 11.0.3. When I connect the phone to my computer running Ubuntu 16.04, I select "Trust" on the phone screen, and it automatically mounts in Ubuntu. When I open the window, it says there are digital photos on the device, but the window shows no files. When I look at the properties of the device, it shows 25.4 GB used but states the "contents" as "nothing". When I open Shotwell, the iPhone appears as a device, but I get Could not claim the USB device (-53) and Unable to fetch previews from the camera: I/O problem (-7).
If I unmount the phone, nothing seems to change in Shotwell.
I have looked at a lot of other questions, but they all seem to either be asking how to mount the phone at all, or the problem is fixed by unmounting. Any ideas about what I am missing here?