JSFiddle - React, Tailwind, and code Playground

HTML

<button onclick="window.PopupCenter('http://www.sage.co.uk','Sage', 1000, 600);">Popup window</button>

JavaScript

window.PopupCenter = function (url, title, w, h) {
				var dualScreenLeft = window.screenLeft != undefined ? window.screenLeft : screen.left;  
				var dualScreenTop = window.screenTop != undefined ? window.screenTop : screen.top;  
						  
				width = window.innerWidth ? window.innerWidth : document.documentElement.clientWidth ? document.documentElement.clientWidth : screen.width;  
				height = window.innerHeight ? window.innerHeight : document.documentElement.clientHeight ? document.documentElement.clientHeight : screen.height;  
						  
				var left = ((width / 2) - (w / 2)) + dualScreenLeft;  
				var top = ((height / 2) - (h / 2)) + dualScreenTop;  
				var newWindow = window.open(url, title, 'scrollbars=yes, width=' + w + ', height=' + h + ', top=' + top + ', left=' + left);  
			  
				// Puts focus on the newWindow  
				if (window.focus) {  
					newWindow.focus();  
				}  
			}