Requirement blocking modification

Issue Summary

On modification of an addnode field, if the assigned Content types that can be referenced has required elements and those elements doesn't have a value, the modification will be blocked. I don't want those to have a default value so filling garbage is not an option.

I found a workaround, simply unchecked the culprit Content types that can be referenced and save then make the modifications and once they're done, check it back and save.