SharedWorker on Android

this API is documented on MDN

Constructor shape (unchanged by this release; Chrome 148 enables it on Android and WebView):

const worker = new SharedWorker("/workers/shared.js", { name: "shared-1" });
worker.port.start();
worker.port.postMessage("ping");
worker.port.addEventListener("message", (e) => console.log(e.data));

MDN's SharedWorker page covers the full API. Chrome 148 browser-compat data for Android will be reflected once MDN is updated.

at a glance

why it was disabled on Android

SharedWorkers were removed from Android in Chrome 40 (around 2015) due to memory and stability concerns on mobile hardware of that era. As Android devices have improved significantly, the Chromium team re-evaluated and ran an origin trial (Chrome 145–147) to validate stability before shipping to all Android users in Chrome 148.

basic usage

// main.js (multiple tabs can connect to the same worker)
const worker = new SharedWorker('/shared-worker.js');
worker.port.start();

worker.port.addEventListener('message', (e) => {
  console.log('From shared worker:', e.data);
});

worker.port.postMessage({ type: 'hello', from: location.href });

// shared-worker.js
const ports = new Set();

self.addEventListener('connect', (e) => {
  const port = e.ports[0];
  ports.add(port);
  port.start();

  port.addEventListener('message', (e) => {
    // Broadcast to all connected tabs
    for (const p of ports) {
      p.postMessage({ echo: e.data });
    }
  });
});

browser support

see also

• MDN: SharedWorker
• MDN: Using Web Workers
• WHATWG HTML Standard — Shared workers and the SharedWorker interface
• chromestatus.com — SharedWorker on Android (6265472244514816)
• chromestatus: API record 6265472244514816
• chromestatus: milestone=148 listing
• WHATWG HTML issue #11205: SharedWorker lifecycle
• Chromium Issue 40290702
• webstatus.dev: shared-workers
• BCD: api/SharedWorker.json
• chrome-platform-showcase: demos