benchmarks/interaction_paint/capture.mjs

const PORT=9444; const sleep=ms=>new Promise(r=>setTimeout(r,ms));
import { writeFileSync } from 'fs';
const list=await (await fetch(`http://127.0.0.1:${PORT}/json/list`)).json();
const t=list.find(x=>x.type==='page'&&/localhost:5173/.test(x.url));
const ws=new WebSocket(t.webSocketDebuggerUrl); let id=0; const p=new Map();
ws.addEventListener('message',ev=>{const m=JSON.parse(ev.data);if(m.id&&p.has(m.id)){const{r}=p.get(m.id);p.delete(m.id);r(m.result);}});
await new Promise(r=>ws.addEventListener('open',r));
const send=(method,params={})=>new Promise(r=>{const mid=++id;p.set(mid,{r});ws.send(JSON.stringify({id:mid,method,params}));});
await send('Page.enable');
const {data}=await send('Page.captureScreenshot',{format:'jpeg',quality:72});
writeFileSync('/tmp/cs4g_app_n1.jpg', Buffer.from(data,'base64'));
console.log('saved /tmp/cs4g_app_n1.jpg');
process.exit(0);