demo · v144 · privacy

High-entropy Hints Probe

High-entropy UA-CH hints (model, full version list, architecture) now require a Permissions Policy delegation to be returned in third-party iframes. Run the probe below to see which hints actually resolve in this top-level context.

userAgentData.getHighEntropyValues: checking…

hintvalue
click to query. In a third-party iframe without Permissions-Policy delegation, every value comes back empty.

the API

// page header
Permissions-Policy: ch-ua-model=(self "https://embed.example.com")

// page or embed JS
const ua = await navigator.userAgentData.getHighEntropyValues([
  "architecture", "bitness", "model", "platform",
  "platformVersion", "fullVersionList", "wow64"
]);
// In a non-delegated iframe these come back as empty strings.

see also