Want To Change Dropdown View

hi 2 all

i want to extend dropdown and change its view ie i want to add button named add new after showing 5 records in dropdown and for other records there is scrool and i want to add TYPEAHEAD at the start of the dropdown so when i enter text the dropdown start filtering data

Plz help me soory to say i am unable to find proper help on this forum

Regards

Fahad

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