Where? I went to https://www.symantec.com/ in Chrome Stable 63.0.3239.140 and didn't see any entries in the dev console about the CA being untrusted or anything like that.
EDIT: I'm an idiot, it didn't occur to me that Symantec didn't sign their own cert. But they don't, it's from DigiCert. Can anyone link to a site that uses Symantec certs?