How to Allow Pop-Ups for a site
Chrome
To see blocked pop-ups for a site, follow the steps listed below:
...
- Click the Chrome menu
on the browser toolbar.
- Select Settings.
- Click Show advanced settings.
- in the "Privacy" section, click the Content settings button.
- In the "Pop-ups" section, click Manage exceptions.
Firefox
When blocking a pop-up, Firefox displays an information bar (if it hasn’t been previously dismissed – see below), as well as an icon 
in the address bar.
...
When you click either the button in the info bar or the icon in the address bar, a menu is displayed with the following choices:
- (show the blocked pop-up)
Internet Explorer
Take these steps to set the options you are seeking:
- In the Start menu's search box, type internet, then choose Internet Options from the search results
- On the Privacy tab, click the settings button next to the Popup Blocker settings (near the bottom).
- You'll be able to list the sites you want to be able to allow popups from. Just list your one site there, then click OK to save.
Safari (macOS)
Safari for macOS has no per-website control over blocking pop-up windows. Pop-ups are either blocked, or they are not. To allow pop-ups:
- From the Safari menu, choose Preferences... and click the Security tab.
- Ensure the Block pop-up windows option is not checked. Unchecking this option will allow pop-ups.
- To block pop-ups once again, check the Block pop-up windows checkbox.
Note: If you are concerned about allowing pop-ups globally for all websites that you browse, consider using another web browser that allows website exceptions such as Chrome or Firefox.