It would appear that after editting a MassMessage delivery list description (a page with such content model) its cache is not purged, causing the whole page to display as empty.
Steps to reproduce:
- Go to e.g. https://meta.wikimedia.org/wiki/User:MarcoAurelio/MM-bugtest and hit edit: https://meta.wikimedia.org/wiki/Special:EditMassMessageList/User:MarcoAurelio/MM-bugtest
- Add something to the Description field, then save.
- The page is updated and the updated content is displayed.
- The page content vanishes and can only be restored by manually purging the page cache (?action=purge)
|Before editting||After editting|