TODO in a tweet
HTML
<script src="https://unpkg.com/umbrellajs"></script>
<script>b=u("body").append(u("<input>").on("keyup",e=>{t=e.currentTarget;if(13==e.keyCode){b.append(`<p><label><input type="checkbox"> <span>`+t.value);t.value=''}})).append(u('<button>Clear').on('click',e=>u('p').remove()))</script><style>:checked+*{text-decoration:line-through}