Wait for LSN

<div class="demo"><div class="head"><b>WAIT FOR LSN 104</b><span>PG 19 beta</span></div><div class="stage waiting"><div class="progress"><div class="fill" id="lsnfill"></div></div><div class="cell" id="readgate">SELECT waits</div></div><div class="foot"><span id="lsnstatus">replica LSN 102</span><span>read your writes</span></div></div>

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let n=0;function tick(){let l=102+n;document.getElementById('lsnfill').style.width=(25+n*37)+'%';let gate=document.getElementById('readgate');gate.textContent=n===2?'SELECT runs':'SELECT waits';gate.classList.toggle('on',n===2);document.getElementById('lsnstatus').textContent='replica LSN '+l;n=(n+1)%3}tick();const t=setInterval(tick,750);document.querySelector('.demo').onclick=()=>{clearInterval(t);tick()}