The pop up blocker has been now removed?
I originally posted something but then realized you were referencing High Sierra and then I removed my post, hence Deleted. Let you ask you this, when you are on a website and you right-click on the address bar does it bring up the following menu?
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While on a webpage, right-click on the address bar, select Settings for This Webpage..., for Pop-up Windows:, select either Block and Notify, Block or Allow.
Also, see if this helps.
How to Stop Annoying Pop-ups in Safari
Safari supports built-in pop-up blocking, but the way to configure it differs depending on whether you're on a Mac, Windows, or iOS device.www.lifewire.com
If you browse to a website (e.g. macrumors.com) and open Safari→Preferences→Websites, do you see the website listed under Currently Open Websites section?
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