Steps to block pop-ups on a Mac computer's Safari browser:

• Launch Safari.
• Select Preferences from the Safari drop-down menu.
• Check the option for Block pop-up windows under the Security symbol at the top.
• You're done! Safari is now pop-up-free!

block pop-ups for specific sites on Mac

• Launch Safari.
• Select Preferences from the Safari drop-down menu.
• On the left, click Pop-up windows under the Websites heading. In the Currently Open Websites section, the website you're on will be listed. Choose Block from the arrows to the right of Block and Notify.
• Pop-ups will no longer be allowed on the website you've selected.
• When Safari is configured to 'Block and Notify,' you can pick the two boxes in the address bar to allow pop-up windows right after they've been blocked.

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