Refreshing marks read items as unread

[ford--prefect]

Checklist

• [x] I've already searched in existing issues and haven't found a similar problem reported.
• [x] I'm using the latest version of the app
• [ ] This error caused the app to crash
• [x] This error is reproducible

Which category best fits this error?

User Interface

App version

0.14.4

Reproduction steps

1. Have a number of unread items in your list, and unsynchronized items upstream.
2. Read an item (or mark it read)
3. Synchronize feeds
4. notice that the previously read item is now unread again

Expectation: Items should only be added on sync, existing items should not be changed in state.

[An-anonymous-coder]

I've reproduced this under different conditions. It's quite annoying.