If you’re talking about the tips at the top of the DNS page (like “Add an A record for www”), Show/Hide just expands or collapses that section for me. I still see the header “A few more steps are required to complete your setup” when collapsed. Maybe you’ve implemented them all?
I believe Email Security is being rolled out. It just appeared for me as a tip on the DNS page and also with its own little “Email Security” box further down.
“The feature will first be rolled out to users on the Free plan and over the next weeks be made available for Pro, Business and Enterprise customers, as well.”