Custom fields and custom table are both created via Web UI, no code.
These are normal text fields with both properties 'Cloneable' and 'Clone as multiple' checked. However, in the database, the clone fields are still stored as serialized array.
Since the option to Clone as multiple is made available in the Web UI, I assume this feature should be functional. In my testing, Clone as multiple works for standard tables (non-custom).
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