I have 2 staging sites using the same hosting website and plan, one where the new builder preview works, one where it doesn't.
On MarisaMolinaro.GrowWithTrueNorth.com, everything is good.
On EyEHomes.GrowWithTrueNorth.com, first it says the security certificate is invalid. Then, when I push through, it refuses to load the preview on the builder. I've tried using different browsers (Safari and Chrome), updating/restarting my computer, the works.
Have my team confirming now if we use Siteground, but I'm pretty sure this a GoDaddy hosted site.