Adding New Certificates
To add a certificate in the simple PEM or DER file formats to the list of CAs trusted on the system, copy the certificate file to the `/usr/share/pki/ca-trust-source/anchors/` or `/etc/pki/ca-trust/source/anchors/` directory, for example:
# cp _~/certificate-trust-examples/Cert-trust-test-ca.pem_ _/usr/share/pki/ca-trust-source/anchors/_
To update the system-wide trust store configuration, use the [command]`update-ca-trust` command:
# update-ca-trust
While the Firefox browser is able to use an added certificate without executing [command]`update-ca-trust`, it is recommended to run [command]`update-ca-trust` after a CA change. Also note that browsers, such as Firefox, Epiphany, or Chromium, cache files, and you might need to clear the browser's cache or restart your browser to load the current system certificates configuration.