https://en.code-bude.net/2017/05/03/how-to-fix-ssl-error-61-in-citrix-web-receiver-on-linux/
sudo ln -s /usr/share/ca-certificates/mozilla/* /opt/Citrix/ICAClient/keystore/cacerts
undo:
cd /opt/Citrix/ICAClient/keystore/cacerts
sudo find -type l -delete