jharding/scrollable-dropdown-menu.css

## scrollable-dropdown-menu.css
#scrollable-dropdown-menu .tt-dropdown-menu {
  max-height: 150px;
  overflow-y: auto;
}

## scrollable-dropdown-menu.html
<div id="scrollable-dropdown-menu">
  <input class="typeahead" type="text" placeholder="Countries">
</div>

## scrollable-dropdown-menu.js
$('#scrollable-dropdown-menu .typeahead').typeahead(null, {
  name: 'countries',
  limit: 10,
  source: countries
});