Can you read favicons from JavaScript or from the server side? I know you can se... | Hacker News

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		jonsolo on Feb 7, 2021 \| parent \| context \| favorite \| on: Supercookie: Browser Fingerprinting via Favicon Can you read favicons from JavaScript or from the server side? I know you can set them from JS, don’t know about reading. If so could you use steganography to encode a unique ID into the icon itself, then read it back to retrieve the fingerprint.

jonasstrehle on Feb 7, 2021 [–]

This idea was indeed my first approach, but favicons on the client side cannot be loaded from the F-Cache via JavaScript, but are ALWAYS requested from the server via get-request, which fortunately thus does not allow fingerprinting. ~jonas

jonsolo on Feb 7, 2021 | [–]

Makes sense, and I agree that is good behavior! Thanks for clarifying.

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