StartpodDocs

Browser requirements

Check the browser capabilities Startpod requires before booting the runtime.

Startpod checks capabilities instead of relying on a user-agent string. It refuses to boot when the browser or host configuration cannot support the runtime.

The page must provide:

  • crossOriginIsolated === true
  • SharedArrayBuffer
  • Atomics.wait and Atomics.waitAsync
  • Web Workers
  • Service Workers
  • MessageChannel
  • structuredClone
if (!window.crossOriginIsolated) {
  showUnsupportedMessage("This page is not cross-origin isolated.")
}

Startpod throws ERR_SP_NOT_CROSS_ORIGIN_ISOLATED when the page headers are wrong. A missing browser capability produces ERR_SP_BROWSER_SUBSTRATE_UNSUPPORTED with the missing features.

Supported browsers

Use a Chromium-based browser, such as Chrome or Edge. Firefox and Safari provide the required base APIs in recent versions, but are not supported for a complete Startpod workflow.

Safari is not supported for a complete Startpod workflow. Use Chrome or Edge for the examples in these docs.

See Browser support for the support matrix and Configure headers for the required response headers.

Access the network

Understand which requests a project can make directly from the browser.

Configure isolation headers

Serve the Startpod host page with the headers required for SharedArrayBuffer and worker isolation.

On this page

Supported browsers