[tzs]

Chrome on MacOS does use the Mac's built-in system. Going to the privacy settings (chrome://settings/privacy), and clicking "Manage certificates" just launches the MacOS "Keychain Access" application.

To get Chrome on MacOS to use my employer's self-signed root certificate, I just had to import it with "Keychain Access" and then both Chrome and Safari used it.

It may also have its own built-in certificate system, but for user-added certificates, it uses the built in MacOS system.