phra / zero-width-fingerprint-detection-extension

A browser extension to detect when zero-width characters are used to fingerprint cut/copied/pasted text.

Zero-Width-Fingerprint-Detection-Extension

This add-on injects JavaScript into web pages. The addons.mozilla.org domain disallows this operation, so this add-on will not work properly when it's run on pages in the addons.mozilla.org domain.

What it does

This extension includes:

• a content script, "content-script.js", that is injected into all pages

The content script listens for cut/copy/paste events in the page it's attached to and it inspect the data to look for zero-width characters that can be used to insert hidden watermarks in the copied text.

Note

• If the copySelection function was in a browser event clipboardWrite permissions would be required e.g.

"permissions": ["clipboardWrite"]

See Interact with the clipboard.