eZ Platform 1.11 and legacy 2017.08 introduced feature for being able to limit classes editor can select during editing on Relation field, as was already possible in RelationList from before.
Unfortunately the implementation differs slightly between platform and legacy, platform code adopted more of the logic from RelationList then the implementaion for legacy did, so if you:
- Edit content type in legacy, platform will get error on content display stopping it from working
- Edit content type in platform, then legacy will be loosing info on selection method and selection root.
Reason is Platform puts all of this info in xml now, like RelationList, while legacy only uses xml for the new feature (content type limitation).