Reproduce in the following way:
1. Go to http://musicbrainz.org/release/e2310769-2e68-462f-b54f-25ac8e3f1a21
2. Edit the release
3. Hit the tracklist tab
4. Expand disc 1
5. Click "Track Parser"
6. Delete two letters in each track name (ie. -XX after the chapter name)
7. Hit Done
8. Collapse disc 1
9. Expand disc 1
Boom. The tracks have gone.
This seems to also break when single tracks are edited - edited tracks get removed on collapse/expand.