-If this policy is set to any value, Firefox reads certificates from the system certificate store. This is currently only supported on Windows, but will be available on macOS with Firefox 63.
+This policy can be used to install certificates or to read certificates from the system certificate store on Mac and Windows. Certificates can be located in the following locations:
+- Windows
+ - %USERPROFILE%\AppData\Local\Mozilla\Certificates
+ - %USERPROFILE%\AppData\Roaming\Mozilla\Certificates
+* macOS
+ - /Library/Application Support/Mozilla/Certificates
+ - ~/Library/Application Support/Mozilla/Certificates
+* Linux
+ - /usr/lib/mozilla/certificates
+ - /usr/lib64/mozilla/certificates
+ - ~/.mozilla/certificates
+
+In Firefox 65, you can specify a fully qualified path.
+