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How can I find out what extensions (not plugins) are currently installed using JavaScript?

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  • Last reply by cor-el

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I am creating a JavaScript module which detects if a Firefox extension is installed in the client's browser.

I can check if a Firefox plugin is installed by querying navigator.plugins object, but I can't figure out how to do this for extensions.

I am creating a JavaScript module which detects if a Firefox extension is installed in the client's browser. I can check if a Firefox plugin is installed by querying navigator.plugins object, but I can't figure out how to do this for extensions.

Chosen solution

You can't check for extensions that are installed.
Plugins can be detected via navigator.plugins as you posted, but you can't detect extensions for privacy and security reasons.


It the past it was possible to check for images added by an extension, but that access was blocked.

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For that kind of help you should see the documentation at MDN - https://developer.mozilla.org

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Chosen Solution

You can't check for extensions that are installed.
Plugins can be detected via navigator.plugins as you posted, but you can't detect extensions for privacy and security reasons.


It the past it was possible to check for images added by an extension, but that access was blocked.