After having upgraded a 5.4 to 2016.02, following the procedures from the doc
while testing EZP-25290, I came across a problem:
a few Content Types that were existent already on 5.4 migrated to Platform losing their Name values and fieldtype Name values in the process.
The Content Types to which this checked out were comment, folder, user, user group and the ones inside Setup content type group.
I have tried to go to Content Type definition and republish, for instance folder and comment, by re-providing it fieldtype names, as they were on an updated 5.4, for instance. This didn't work either because I got the notification error "Form did not validate. Please review errors below." and field inline notifications "Field definition name cannot be blank cannot exceed 255 characters.", one for each field, even though all were filled correctly, and even got a 200 OK Response for the POST Request when checking dev tools, as well as on the request's Params tab all fields are in fact filled.
This proves being unable completely to create contents of these Content Types at all.