Go to the website.
Choose Safari > Settings, then click Websites.
Click Pop-up Windows on the left.
If you don’t see Pop-up Windows, be sure to scroll to the bottom of the list.
In the pop-up menu for the website, choose one of the following:
Block and Notify: Pop-ups for the website don’t appear, but when you visit the website, you can choose to show them by clicking on your Mac.
If there are websites listed below Configured Websites, and you want to change the settings for these sites (for example, they’re set to Block, but you want to change them to Allow), select each website, then click Remove.
If you don’t see Configured Websites, either you haven’t set pop-up blocking for any sites yet, or you’ve cleared the list.
Click the “When visiting other websites” pop-up menu, then choose Allow.
Go to the Safari app Hide distractions when reading articles in Safari on Mac