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Preview of SSLeuth

SSLeuth by mcortt

Instantly view any website's security status. SSLeuth provides a detailed, color-coded popup showing TLS connection details and the full certificate chain, helping you quickly identify connection warnings or issues. Works on Firefox for Android too!

Available on Firefox for Android™Available on Firefox for Android™
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Extension Metadata

Screenshots
Connection Details (Secure) - DesktopCertificate Details - DesktopConnection Details (Weak) - DesktopConnection Details (Broken)- DesktopToolbar Icon (Secure) - DesktopToolbar Icon (Weak) - DesktopToolbar Icon (Broken/Insecure) - DesktopIcon (Secure) - AndroidIcon (Broken/Insecure) - AndroidConnection & Cert Details (Secure) - AndroidConnection Details (Broken) - AndroidConnection Details (Insecure) - Android
About this extension
An open-source browser extension that provides a detailed, easy-to-read view of any website's TLS/SSL certificate and connection security.

Why SSLeuth?

Modern browsers, especially on mobile, often hide important security details. SSLeuth brings this crucial information back, allowing developers, security professionals, and curious users to see exactly how their connection is secured.

Features
  • At-a-Glance Security Status
    > A prominent, color-coded badge clearly labels the connection as SECURE (Green), WARNING (Yellow), or INSECURE (Red). It provides a simple, clear reason for any non-secure status.
  • Detailed Connection Analysis
    > Get a complete picture of the TLS connection with details that are normally hidden, including the HTTP protocol version, cipher suite, key exchange group, HSTS status, and more.
  • Full Certificate Chain Inspection
    > Dive deep into the certificate chain with a clean, collapsible interface. Each certificate's Subject, Issuer, Validity Period, and Fingerprints are parsed into an easy-to-read format.
  • Robust and Accurate
    > SSLeuth uses background listeners to capture security information directly from network requests and intelligently handles cached navigations (like using the back/forward buttons) to prevent showing stale data.
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Permissions and dataLearn more

Required permissions:

  • Access browser tabs
  • Access your data for all websites
More information
Add-on Links
  • Homepage
  • Support site
Version
1.7.1
Size
15.52 KB
Last updated
19 days ago (Jul 29, 2025)
Related Categories
  • Privacy & Security
License
GNU General Public License v3.0 only
Version History
  • See all versions
Tags
  • privacy
  • security
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Release notes for 1.7.1
Fixed an issue with icon not updating for broken/insecure sites.
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