Hey there, the newest version of MB wiped all my fields, both for settings pages, ones coded into my theme, and ones created with the builder. How can I resolve this quickly!
I'm having a similar issue, I don't know if it's the same as OP's.
It is affecting a Field Group with nested + cloneable "groups" of fields. The custom fields don't load when editing the field group, ever since 1.13. I have tried the migration parameter and no luck. Other field groups load in the new interface (no nested groups)...
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