Open Safari. Click the compass-shaped app icon in your Mac's Dock. Click Safari. This menu item is in the top-left corner of the screen. A drop-down menu will appear. Click Preferences…. It is near the top of the drop-down menu. Doing so prompts a window to open. Click the Security tab. You will find it at the top of the window. Uncheck the "Block pop-up windows" box. It is in the "Web content" section of this menu. This will disable Safari's pop-up blocker. (More information) Close the window and restart Safari. Doing so will save your changes. You should now be able to view pop-ups in Safari.