This is a working list for me and perhaps you.
SEO- JSON+LD
They love JSON+LD for those cute little previews you see in text messages and in [insert communication messaging tool]. So, how they work? JSON+LD. Go to https://schema.org for the deets and all of the possibilities.
- Google's checker, McWrecker: Rich Results Test - Google Search Console. Make sure you did it right and what it noticed - after all, he's still the boss. https://search.google.com/test/rich-results
- NuGet for us C#ers - https://github.com/idenys/MXTires.Microdata is pretty good and hasn't failed me. And then you don't need to worry about @ in Razor pages 😒
Security
After you make sure you have all the good settings and ready to deploy, make sure you test it on a throw-away-domain or slot. Cause, this can wreak havoc on a prod site. And with things like HSTS and 301 permanents, you'll suffer for a while.