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  2. Add-ons
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  4. JavaScript APIs
  5. extension
  6. extension.inIncognitoContext

extension.inIncognitoContext

Boolean value, true for content scripts running inside private browsing tabs and for extension pages running inside a private browsing process.

Syntax

js
let isPrivate = browser.extension.inIncognitoContext;  // true or false

Value

A boolean value indicate if the current script is running in a private tab or process.

Browser compatibility

Chrome
Edge
Firefox
Opera
Safari
Firefox for Android
Safari on iOS
inIncognitoContext
Chrome – No support
Chrome 5 – 66 (Release date: 2010-05-25)
altname
footnote Removed in 67 and later
altname Alternate name: inIncognitoTab
footnote Only supported in manifest v1.
Chrome – Full support
Chrome 7 (Release date: 2010-10-19)
footnote Full support
Edge – Full support
Edge 17 (Release date: 2018-04-30)
footnote Full support
Firefox – Full support
Firefox 45 (Release date: 2016-03-08)
footnote Full support
Opera – No support
Opera 15 – 53 (Release date: 2013-07-02)
altname
footnote Removed in 54 and later
altname Alternate name: inIncognitoTab
footnote Only supported in manifest v1.
Opera – Full support
Opera 15 (Release date: 2013-07-02)
footnote Full support
Safari – Partial support
Safari 14 – 17.6 (Release date: 2020-09-16)
footnote Partial support
footnote Always returns false.
Safari – Full support
Safari 18 (Release date: 2024-09-16)
footnote Full support
Firefox for Android – Full support
Firefox for Android 48 (Release date: 2016-08-02)
footnote Full support
Safari on iOS – Partial support
Safari on iOS 15 – 17.6 (Release date: 2021-09-20)
footnote Partial support
footnote Always returns false.
Safari on iOS – Full support
Safari on iOS 18 (Release date: 2024-09-16)
footnote Full support

Tip: you can click/tap on a cell for more information.

Full support
Partial support
Uses a non-standard name
Has more compatibility info.

Note: This API is based on Chromium's chrome.extension API. This documentation is derived from extension.json in the Chromium code.

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