Linux import AD certificate for chromium

I use Chromium on ubuntu to access websites within our company intranet.  The websites are secured with a certificate created by an internal CA server.

Chromium does not allow me to install/store the certificate, so I have to click Advanced > Proceed to website (unsafe) when the "Connection is not Private" page appears.  Obviously, this works until the timeout / cached answer expires and I'm prompted again.  While this was a minor issue in the beginning, I have grown tired of this nag and am looking for a long term solution.

What will fix this issue?  Do I have to join my linux workstation to the domain?  Is there a way to install the certificate to shut chromium up?  Is it possible to disable this warning for intranet pages?  Btw, this server has no outside internet access, so I'm not concerned with any potential anti-security options.