Chrome no longer lets you export a certificate. You need to either use another browser that supports this function (for example, Firefox), or simply copy the generated certificate to the shared directory from your home computer so that you can then import it and trust it in the keychain.
# where I share all homestead certs with the host machine mkdir /home/vagrant/Code/.certs/ cp -vf /etc/nginx/ssl/homestead.app.cert /home/vagrant/Code/.certs
On the local host, open the certificate file and import it into the system keychain. After importing, open it and set the trust level to "Always trust."

Restart Chrome and you're done.
source share