Note: Certainly Something has been integrated into Firefox 72, and is no longer necessary for viewing certificates.
Uses the new TLS Info API in Firefox to view information about the current state of your HTTPS connection.
It currently requires at least Firefox 62.
It is recommend that developers use web-ext for installation and testing. It provides a number of useful features, such as automated installation and autoreload upon source changes.
Install web-ext using the following command:
$ npm install --global web-ext
For testing and development, run the following commands in two separate terminal windows:
$ npm run-script watch
$ web-ext run --browser-console -s build --start-url 'https://badssl.com/'
If you are simply looking to give it a single run, you can compile it by running:
$ npm install
$ npm run-script compile
And then in Firefox, go to -> Add-ons -> Extensions -> (Gear Icon) -> Debug Add-ons -> Load Temporary Add-on
Navigate to build/manifest.json
and it should start running immediately.
Thanks so much to Ryan Hurst and Yury Strozhevsky for doing the painful work in PKI.js and ASN1.js, without which this project could not have been accomplished.