Reply To: "mb_user_meta & mb_rest_api" has problem

Hi Jiro, you're right about the missing user in the update_user_meta call. I've just added that fixed.

Regarding the var_dump, it's not strange as the field registry (where all fields are stored) is structured like this:

object_type
  specific_type
    field 1
    field 2

For posts, object_type is post and specific_type is post type. For terms, it's term and taxonomy. For users, as there's no specific type, we use user and user.