Well, you are using javascript anyway so here it is a 163 bytes solution without the back button problem and iframe hack: <script>onclick=async e=>{x=e.target.

Well, you are using javascript anyway so here it is a 163 bytes solution without the back button problem and iframe hack: <script>onclick=async e=>{x=e.target.dataset.x;if(x){e.preventDefault();document.querySelector(x).innerHTML=await fetch(e.target.href).then(r=>r.text())}}</script> <a href="/somepage" data-x="#lib">Hi</a> <div id="lib"></div> doesn't works with form though.