Edit, cancel, edit, cancel, edit, ... broken
I did this as an unregistered user. All I did was hitting edit, cancel, edit, cancel, edit. The value and the editor both disappeared (upper half of the image shows expected, lower half the broken behavior).
I wasn't able to reproduce this on wikidata.org. But it's very easy to reproduce on my development system.
It seems it has something to do with the qualifier I added. In my example the qualifier repeats both the property and the value from the snak.
Version: master
Severity: normal
Whiteboard: u=dev c=frontend p=0
Attached: