TLS Lens by Marco Appoldt

TLS Lens displays the SSL/TLS certificate information for the website you are currently visiting with a single click.

Information displayed:

Connection status (secure, weak, or faulty) with colored banner
TLS version and cipher suite
Extended Validation (EV) status
Certificate Transparency (CT) and OCSP status
Common name (CN) of the certificate
Issuer (organization and CN)
Validity period with visual indicator
Authority Information Access (AIA): OCSP URL and CA Issuers URL
Complete certificate chain as a collapsible tree structure
Error detection:
TLS Lens detects expired certificates, domain discrepancies, and untrustworthy issuers. If certificate errors are found, the icon in the toolbar turns red.

Data protection:
TLS Lens does not collect or transmit any user data. All information is read exclusively from the browser's existing TLS connection and displayed in a pop-up.

Permission explained:
The permission “Access your data for all websites” is required to read the TLS certificate information of each HTTPS connection via the Firefox API webRequest.getSecurityInfo(). No website content is read or modified.