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SignatureCheck.org Certificate Thumbprint Validator 1.1
Validates certificates against thumbprints retrieved from SignatureCheck.org.
Warns user when differences are detected.
About this Add-on
This can detect man-in-the-middle attacks that use valid signing certificates because the connection to SignatureCheck.org is protected by a key independent of the PKI trusted by the browser.
It can also check self-signed certificates to provide validation for websites that use them.
For more information, visit SignatureCheck.org