You can do the same thing with any type of field. For a text area instead of setting $field[‘message’] you would set $field[‘value’]. I was under the assumption that you just wanted to be able to copy and paste the value. If you want to use the value is some other way then you would need a different type of field. But this is really not needed, if you want to use the values of the other fields outside of the admin you just need to get the values and combine them.
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