TeamGale added some citations and then saved the page. She received an "unknown error" and assumed that the page did not get saved. So she saved the page again. Upon checking the history, she found that both attempts to save the page had resulted in a new version:
However, the first diff removed the end of the page, including the reference secyion, external links, navboxes, succession boxes, categories, and more. These were automagically restored when she saved the second time.
Reproducible: Didn't try
TeamGale usually edits with Firefox 28 on Windows 8.