On https://fr.wikipedia.org/wiki/Ardent_Group if we try to move a reference (drag and drop), it just disappears.

There is no undo history and no way to save it. Except if we edit something first.

To reproduce:

1. Add some text in the article
2. Move the reference 3 between the 1 and 2
3. Try to save

Result:
The reference 3 gets removed.