JSON circular reference detected error

[mtrebron (Norbert)]

Thank you! Much cleaner than the solution I came up with.

RelationList with SelectFieldWidget: ValueError: Circular reference detected

I have been using this monkey patch for a long time: <monkey:patch description="Fix circular reference when field is RelationValue" class="plone.app.content.utils" original="custom_json_handler" replacement=".monkey_patches.pac_utils_custom_json_handler" /> def pac_utils_custom_json_handler(obj): #log.info('%s custom_json_handler called' % get_linenumber()) if obj == Missing.Value: return None if type(obj) in (datetime.datetime, datetime.da…