megachangelog
Feature

Browser Run - Multiple concurrent clients per session

Browser Run sessions now accept multiple concurrent connections instead of one at a time, allowing multiple Workers to connect to the same browser simultaneously. Each connection uses separate browser contexts to isolate pages, cookies, and storage, reducing cold-start time and browser limits.

Browser Run sessions now accept multiple concurrent connections. Before, a session accepted only one connection at a time, and other Workers had to wait until that connection closed. Now multiple Workers can connect to the same browser at the same time.

Each puppeteer.connect() call opens its own Chrome DevTools Protocol (CDP) connection. Create a separate browser context for each request to keep its pages, cookies, and storage apart from other clients.

const browser = await puppeteer.connect(env.MYBROWSER, sessionId);
const context = await browser.createBrowserContext();

try {
	const page = await context.newPage();
	await page.goto("https://example.com");
	// ...
} finally {
	await context.close();
	await browser.disconnect(); // keep the shared browser running
}
const browser = await puppeteer.connect(env.MYBROWSER, sessionId);
const context = await browser.createBrowserContext();

try {
	const page = await context.newPage();
	await page.goto("https://example.com");
	// ...
} finally {
	await context.close();
	await browser.disconnect(); // keep the shared browser running
}

Sharing sessions means fewer new browsers to launch, less cold-start time, and fewer concurrent browsers counted against your limits.

Concurrent connections require @cloudflare/puppeteer version 1.1.0 or later.

Refer to Reuse sessions for a full example.

browser-runpuppeteerworkersfeature

Source: original entry ↗

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