To allow websites to show pop-up windows in Microsoft Edge, you have to disable the browser's pop-up blocker. Here's how you do that on desktop and mobile. Why Disable the Pop-Up Blocker in Edge?

In Firefox on Windows, when the yellow 'prevented this site from openening' window appears, you can click on it and get several options: <BR>* Allow popups from this host<BR>* edit popup blocker ...