This feature is well established and works across many devices and browser versions. It’s been available across browsers since April 2018.
Note: This feature is only available in Service Workers.
The frameType read-only property of the Client interface indicates the type of browsing context of the current Client. This value can be one of "auxiliary", "top-level", "nested", or "none".
One of these four strings: "auxiliary", "top-level", "nested", or "none".
| Specification |
|---|
| Service Workers> # client-frametype> |
| Desktop | Mobile | |||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Chrome | Edge | Firefox | Opera | Safari | Chrome Android | Firefox for Android | Opera Android | Safari on IOS | Samsung Internet | WebView Android | WebView on iOS | |
frameType |
43 | 17 | 44 | 30 | 11.1 | 43 | 44 | 30 | 11.3 | 4.0 | 43 | No |
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https://developer.mozilla.org/en-US/docs/Web/API/Client/frameType