JSFiddle - React, Tailwind, and code Playground

HTML

<input id="autocomplete"/>&nbsp;<input id="submit" type="submit" disabled="disabled"/>

JavaScript

var source = ['One', 'Two', 'Three', 'Four'];

$("input#autocomplete").autocomplete({
    source: source,
    select: function(event, ui) {
        $("#submit").removeAttr("disabled");
    }
}).change(function() {
    var $parentContext = $(this);
    var matches = $.grep(source, function(n, i) {
        return $parentContext.val().toLowerCase() == n.toLowerCase();
    });
    $("#submit").attr("disabled", !matches.length);
    
});