The problem happens because is_hidden column, which is used in the Legacy/Content/Location/Gateway/DoctrineDatabase::isHiddenByParent() method is not in the selection list of the query thaht fetches the data.
The problem is commented on the PR: https://github.com/ezsystems/ezpublish-kernel/pull/1528#discussion_r256697859
Steps to reproduce (2.4.1):
- In symfony env dev.
- Create 3 folders in Home, on under the other.
- Go to the second, middle one and change its Visibility to hidden.
- Go to the third, last one (which is hidden by superior / parent) and try to move it to another folder (screen 1).
Actual result: Folder is not moved, error occurs in UI "Notice: Undefined index: is_hidden" (screen 2).
Remarks: Could not reproduce in prod env. Moving the first and second folder works.