No couple-of-buttons way. This has three parts, one easy, one hard, one custom.
The COMPARE command can show what files got added, deleted, or modified.
This is a little better than file statistics in job log, but doesn’t detail file changes.
Anything trying to do that would probably have to work based on the file format.
Historically, Duplicati didn’t pay attention to file type, except for its compression.
Duplicati, Inc. seems to be launching an effort that sounds more content aware.
Beyond Backup: The Evolution of Institutional Memory
Maybe we’ll hear more details someday. It also sounds a bit enterprise-oriented.
I don’t think there’s any integration of Compare and Restore, but here are ideas:
Above was Windows. If you’re on Linux (or such), your scripting tools are better.
This is almost (or maybe) the kind of project that xargs could help to automate.