TLS 1.3 default for new protocols

<div class="n-demo"><div class="n-head"><strong>NEW PROTOCOL · TLS POLICY</strong><span>LIVE TRACE</span></div><div class="n-stage"><div class="min-tls"><div class="n-box">NEW PROTOCOL</div><div class="min-branch"><div id="mt13" class="n-box">TLS 1.3<br><small>DEFAULT</small></div><div id="mt12" class="n-box">TLS 1.2<br><small>OPTIONAL</small></div></div><div id="mt-note">default route → 1.3</div></div></div><div class="n-foot">tap to step · auto replay</div></div>

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let step=0;function advance(){document.getElementById('mt13').classList.toggle('n-on',step!==2);document.getElementById('mt12').classList.toggle('n-on',step===2);document.getElementById('mt-note').textContent=step===2?'optional compatibility → 1.2':'default route → 1.3';step=(step+1)%3}
const clickTarget=document.querySelector('.n-demo');if(clickTarget&&typeof advance==='function'){advance();const timer=setInterval(advance,1050);clickTarget.addEventListener('pointerdown',()=>{clearInterval(timer);advance()})}