PQSpy

Firefox extension to quickly check if the webpage you're visiting was protected using post-quantum encryption.

Installation

1. Go to about:addons
2. Click the gear, and then Debug Add-Ons.
3. Press Load Temporary Add-on.
4. Browse to manifest.json.

Also don't forget to turn on PQC (Kyber):

5. Go to about:config and set security.tls.enable_kyber (and network.http.http3.enable_kyber if present) to true.

⚠️ As of writing, Firefox does not support PQC over HTTP/3 (yet), so you might see false negatives. ⚠️

(PQC over HTTP/3 will will land in Firefox 126. Available in nightly.)