custom_values=on means someone should be able to type their own value into that box.
dynamic_choices=on means that when someone types their own value into the box (and submits the entry), assuming the entry still exists, that value should then become an available choice in the dropdown for future submissions.
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#5994 - custom_values=on,dynamic_choices=on but no custom values
custom_values=on means someone should be able to type their own value into that box.
dynamic_choices=on means that when someone types their own value into the box (and submits the entry), assuming the entry still exists, that value should then become an available choice in the dropdown for future submissions.