Drop-down list without Javascript
Demo
Start typing to get suggestion.
Code
<input type="text" list="cities-list" /> <datalist id="cities-list"> <option value="Bakar" /> <option value="Beli Manastir" /> <option value="Belišće" /> <option value="Benkovac" /> … </datalist>
Support
All major browsers.
Safari since 12.1 (March 2019).