File being skipped by Restore Point operation

I use the QuiteRSS feedreader, and just found that my database of feeds is not being backed up by Systemback.

This screenshot shows the original folder, the backed-up folder, and Systemback's exclusion settings for the folder. You will see "feeds.db" is not backed up, you will see it not listed or excluded under Systemback's exclusion browser. Curiously, SB does see another file, cookies.dat, which doesn't appear in the actual folder.

Restore Point creation just ran, soon after a boot up, when QuiteRSS hadn't been used yet in the session and is not listed under running tasks, so I don't think file locks are part of the problem. When I do a mirror using FreeFileSync, the file is backed up with no problem, but I'd like to get it working using SB.

Thanks much.