Multipath QUIC draft

<div class="n-demo"><div class="n-head"><strong>TWO PATHS · ONE CONNECTION</strong><span>LIVE TRACE</span></div><div class="n-stage"><div class="multi"><div class="multi-path"><span>WI-FI</span><i id="mp0"></i><b id="mp-off">DROP</b></div><div class="multi-path"><span>CELL</span><i id="mp1"></i></div><div id="mp-note">packets use both paths</div></div></div><div class="n-foot">tap to step · auto replay</div></div>

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let step=1;function advance(){const sizes=[[25,20],[50,45],[50,72],[50,94]];document.getElementById('mp0').style.width=sizes[step][0]+'%';document.getElementById('mp1').style.width=sizes[step][1]+'%';document.getElementById('mp-off').style.opacity=step>=2?'1':'0';document.getElementById('mp-note').textContent=step>=2?'Wi-Fi stopped · cellular continues':'packets use both paths';step=(step+1)%4}
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