CipherFox displays the current SSL/TLS cipher, protocol and certificate chain in the Add-on bar and Site Identification dialog.
The Qualys SSL Labs Server Test for the current domain is also accessible from the menu.
CipherFox is supported in Firefox, Pale Moon and SeaMonkey.
You can click CipherFox to show a popup menu with the certificate chain. Clicking on any certificate shows you its detailed properties. Variables are available in the Preferences window to customize the output.
The source code for CipherFox is made available under the Mozilla Public License 2.0 on GitHub: https://github.com/gavinhungry/cipherfox
Earlier versions were released under the MPL 1.1.
CipherFox is distributed by AMO: https://addons.mozilla.org/en-US/firefox/addon/cipherfox/