Originally published on cert-depot.com . Free, open-source self-signed certificate generator — no signup, keys never stored. How to Trust a Self-Signed Certificate in Firefox Firefox ignores the OS trust store by default. Here's how to add your cert to Firefox's own store. Firefox is the only major browser that maintains its own certificate store separate from the operating system. Installing a cert in Keychain (macOS), Certificate Manager (Windows), or /etc/ssl/certs/ (Linux) won't affect Firefox. Option 1: Enable OS trust store Since Firefox 49, you can make Firefox honor the OS trust store via a preference: Open about:config in Firefox. Accept the warning. Search for security.enterprise_roots.enabled . Set it to true . Restart Firefox. Firefox will now trust certificates installed in the OS trust store. This is the easiest option if you've already installed the cert OS-wide.…