.ui-autocomplete {
    max-height: 150px;
    overflow-y: auto;
    /* prevent horizontal scrollbar */
    overflow-x: hidden;
}

.ui-helper-hidden-accessible {
    border: 0;
    clip: rect(0 0 0 0);
    height: 1px;
    margin: -1px;
    overflow: hidden;
    padding: 0;
    position: absolute;
    width: 1px;
}