When initializing a typeahead, you pass the plugin method one or more datasets. The source of a dataset is responsible for computing a set of suggestions for a given query.

For more advanced use cases, rather than implementing the source for your dataset yourself, you can take advantage of Bloodhound, the typeahead.js suggestion engine. Bloodhound is stack, flexible, and offers advanced functionalities such as prefetching, intelligent caching, fast lookups, and backfilling with remote data.

Prefetched data is fetched and processed on initialization. If the browser supports local storage, the processed data will be cached there to prevent additional network requests on subsequent page loads.

Default suggestions can be shown for empty queries by setting the minLength option to 0 and having the source return suggestions for empty queries.

To change the height of your dropdown menu, just wrap your input in some div with custom css styles and change necessary css properties or change it in css directly.