How to reproduce:
- Set the allowed number of versions high enough (4 or more)
- In a course make a single page and edit several time the file to fill the revisions list
- Add some images
- Copy the course
- It's possible (but not sure) that the images will be missing
- The loop which copy the files of directory will breaks if a single don't can be copied.
- Want to copy a file with the name of an existing file lead to an "error".
- Versioned files copy alone the versions
- The container want to copy the versions of the files, cannot
- Give up and miss some files
- The error is never written in log and absolutely silent