Firefox lists not valid certificates as secure

Trying to enhance local network access, I imported the Cloudflare Origin Server certificate. Despite adding it to Windows' Trusted Root Certification Authorities, Chrome flagged a certificate error, labeling the connection insecure. Firefox, however, indicated a secure connection without warnings.

Firefox lists not valid certificates as secure
Photo by Growtika / Unsplash

Recently, I attempted to improve access to my web server within my local network by importing the Cloudflare Origin Server certificate. However, this certificate is specifically designed to be trusted only by Cloudflare. Even after importing it into the Trusted Root Certification Authorities store in Windows, an error message indicated that "Windows does not have enough information to verify this certificate" due to the absence of the complete certificate chain.

Windows does not verify this certificate without a full chain

As a result, Chrome and other Chromium-based browsers displayed a certificate error, marking the connection as insecure.

Certificate is not valid in Chrome

Interestingly, Firefox did not show a warning about the certificate issues; instead, it indicated that the connection was secure despite the unrecognized certificate problems.

Firefox says you are securely connected