Pop-Up Blocker

Simple but effective popup window blocker. Also tries to deny unsolicited redirections.

Fra og med 15.01.2017. Se den nyeste version.

You will need to install an extension such as Tampermonkey, Greasemonkey or Violentmonkey to install this script.

You will need to install an extension such as Tampermonkey or Violentmonkey to install this script.

You will need to install an extension such as Tampermonkey or Violentmonkey to install this script.

You will need to install an extension such as Tampermonkey or Userscripts to install this script.

You will need to install an extension such as Tampermonkey to install this script.

You will need to install a user script manager extension to install this script.

(I already have a user script manager, let me install it!)

You will need to install an extension such as Stylus to install this style.

You will need to install an extension such as Stylus to install this style.

You will need to install an extension such as Stylus to install this style.

You will need to install a user style manager extension to install this style.

You will need to install a user style manager extension to install this style.

You will need to install a user style manager extension to install this style.

(I already have a user style manager, let me install it!)

// ==UserScript==
// @name        Pop-Up Blocker
// @namespace   HTML
// @description Simple but effective popup window blocker. Also tries to deny unsolicited redirections.
// @include     *
// @version     $Id$
// ==/UserScript==

(function () {
	var BLOCK_MODE = {'ALL': 0,  // Block all popups
										'CONFIRM': 2,  // Confirm each popup (not recommended, but useful for testing)
										'GRANT_PERIOD': 4,  // Block popups that are initiated after the mouse click grant period
										'INSECURE': 8}  // Block popups from insecure (HTTP) sites

	// Configuration
	var block_mode = BLOCK_MODE.GRANT_PERIOD | BLOCK_MODE.INSECURE;
	var grant_period = 100;  // Milliseconds
	var debug = false;  // Enable debug logging

	// DO NOT CHANGE BELOW THIS POINT
	var allowed_elements = {'a': 1, 'button': 1, 'input': 1, 'select': 1, 'option': 1};
	var ts = 0, wopen = window.open, showmodaldlg = window.showModalDialog;
	var lastInteractedElement;
	var marginTop = null;
	var notifications = 0;
	var notificationOffsetTop = 0;

	window.addEventListener('mousedown', function (event) {
		ts = Date.now();
		if (debug) console.info('Mouse button', event.button != null ? event.button : event.which, 'down on', event.target);
		setlastInteractedElement(event);
		//mediateEventPropagation(event);
	}, true);

	window.addEventListener('click', function (event) {
		ts = Date.now();
		if (debug) console.info('Mouse button', event.button != null ? event.button : event.which, 'click on', event.target);
		setlastInteractedElement(event);
		//mediateEventPropagation(event);
	}, true);

	window.addEventListener('change', function (event) {
		ts = Date.now();
		if (debug) console.info('Changed selection on', event.target);
		setlastInteractedElement(event);
		//mediateEventPropagation(event);
	}, true);

	function setlastInteractedElement(event) {
		// Deal with tags nested in (e.g.) links
		var element = event.target;
		if (event instanceof MouseEvent && (event.button != null ? event.button != 0 : event.which != 1)) return;
		while (element.parentElement && element.tagName && !allowed_elements[element.tagName.toLowerCase()]) {
			element = element.parentElement;
		}
		lastInteractedElement = element;
		if (debug) console.info('Last interacted element', element);
	}

	function mediateEventPropagation(event) {
		// Stop event propagation if element has a 'href' attribute that does not point to the current document
		// (prevents click hijacking)
		if ((block_mode & BLOCK_MODE.INSECURE ? location.protocol != 'https:' : true) &&
			lastInteractedElement &&
			lastInteractedElement.href &&
			boildown(lastInteractedElement.href) != boildown(window.location.href) &&
			lastInteractedElement.href.indexOf('javascript:') !== 0) {
			event.stopPropagation();
			console.warn('Pop-Up Blocker stopped event propagation for', event);
		}
	}

	function regExpEscape(s) {
		return String(s).replace(/([-()\[\]{}+?*.$\^|,:#<!\\])/g, '\\$1').
			replace(/\x08/g, '\\x08');
	};

	var regExpProtHostPathQ = new RegExp('^((' + regExpEscape(location.protocol) + '//' + regExpEscape(location.host) + ')?' +
										    '(' + regExpEscape(location.pathname) + ')?)?');

	function boildown(uri) {
		var uri_boileddown = uri.replace(regExpProtHostPathQ, '');  // Strip current protocol + host + path
		uri_boileddown = uri_boileddown.replace(/#.*$/, '');  // Strip any hash
		// Sort query vars
		var query = uri_boileddown.match(/\?[^?]+/);
		if (query)
			query = '?' + query[0].substr(1).split('&').sort().join('&');
		uri_boileddown = uri_boileddown.replace(/\?[^?]+/, query || '');
		return uri_boileddown;
	};

	// Deny unsolicited redirection
	if (typeof window.location.watch == 'function') window.location.watch(
		'href',
		function (id, oldval, newval) {
			var href_boileddown, newval_boileddown = boildown(newval);
			console.info('location.' + id, '->', newval);
			if (lastInteractedElement && lastInteractedElement.tagName &&
				lastInteractedElement.tagName.toLowerCase() == 'a')
				href_boileddown = boildown(lastInteractedElement.href);
			var link_hijacked = href_boileddown != undefined && newval.indexOf('#') !== 0 && newval_boileddown != href_boileddown;
				grantperiod_exceeded = (Date.now() > ts + grant_period && link_hijacked);
				
			if ((block_mode & BLOCK_MODE.INSECURE ? location.protocol != 'https:' : true) &&
				(!lastInteractedElement ||
				 (lastInteractedElement.tagName &&
				  (!allowed_elements[lastInteractedElement.tagName.toLowerCase()] ||
				   (lastInteractedElement.tagName.toLowerCase() == 'a' &&
				    (link_hijacked ||
				     lastInteractedElement.target == '_blank')))) ||
				 grantperiod_exceeded)) {
				if (debug) {
					console.info('Page secure?', location.protocol == 'https:');
					console.info('Allow insecure page?', block_mode & BLOCK_MODE.INSECURE ? false : true);
					console.info('Last interacted element?', lastInteractedElement);
					if (lastInteractedElement) {
						console.info('Last interacted element tag name?', lastInteractedElement.tagName);
						if (lastInteractedElement.tagName) {
							console.info('Allowed element?', !!allowed_elements[lastInteractedElement.tagName.toLowerCase()]);
							console.info('Last interacted element is link?', lastInteractedElement.tagName.toLowerCase() == 'a');
							if (lastInteractedElement.tagName.toLowerCase() == 'a') {
								console.info('New location (boiled down) =', newval_boileddown);
								console.info('Link HREF (boiled down) =', href_boileddown);
								console.info('New location is the same as link HREF?', newval_boileddown == href_boileddown);
								console.info('Link target is a new window?', lastInteractedElement.target == '_blank');
							}
						}
					}
					console.info('Grant period exceeded?', grantperiod_exceeded);
				}
				notify('Denied redirection to', newval, null, 0, null, '_self');
				console.error('Pop-Up Blocker denied redirection to ' + newval);
				return '#' + location.hash.replace(/^#/, '');
			}
			return newval;
		}
	);

	var onbeforeunload = window.onbeforeunload;
	window.onbeforeunload = function () {
		// Check if the last interacted element was a link or button, otherwise make browser ask if the user really wants to leave the page
		if (lastInteractedElement && lastInteractedElement.tagName &&
				!allowed_elements[lastInteractedElement.tagName.toLowerCase()] &&
				(block_mode & BLOCK_MODE.INSECURE ? location.protocol != 'https:' : true) && Date.now() <= ts + grant_period) {
			if (debug) {
				console.info('Page secure?', location.protocol == 'https:');
				console.info('Allow insecure page?', block_mode & BLOCK_MODE.INSECURE ? false : true);
					console.info('Last interacted element?', lastInteractedElement);
					if (lastInteractedElement) {
						console.info('Last interacted element tag name?', lastInteractedElement.tagName);
						if (lastInteractedElement.tagName) {
							console.info('Allowed element?', !!allowed_elements[lastInteractedElement.tagName.toLowerCase()]);
						}
					}
					console.info('Grant period exceeded?', Date.now() > ts + grant_period);
			}
			return 'You are possibly involuntarily being redirected to another page. Do you want to leave ' + location.href + ' or stay?';
		}
		else if (typeof onbeforeunload === 'function')
			return onbeforeunload.apply(window, arguments);
	};

	function confirmPopup(msg, args) {
		confirm(msg + ' (' + Array.prototype.slice.apply(arguments).join(', ') + ')');
	}

	window.open = function () {
		var oargs = arguments;
		if (debug) {
			console.info('Page secure?', location.protocol == 'https:');
			console.info('Allow insecure page?', block_mode & BLOCK_MODE.INSECURE ? false : true);
			console.info('Grant period exceeded?', Date.now() > ts + grant_period);
		}
		if (['_self', '_parent', '_top'].includes(arguments[1]) ||
			(block_mode != BLOCK_MODE.ALL &&
				(block_mode & BLOCK_MODE.CONFIRM
				 ? confirmPopup('Allow popup?', arguments)
				 : (block_mode & BLOCK_MODE.INSECURE ? location.protocol == 'https:' : true) && Date.now() <= ts + grant_period))) {
			console.info('Pop-Up Blocker allowed window.open', Array.prototype.slice.apply(arguments));
			return wopen.apply(window, arguments);
		}
		else {
			console.warn('Pop-Up Blocker blocked window.open', Array.prototype.slice.apply(arguments));
			notify('Blocked popup window', arguments[0], arguments[1], 0, function() {
				console.info('Pop-Up Blocker user clicked window.open', Array.prototype.slice.apply(oargs));
				wopen.apply(window, oargs);
			});
		}
		return {}
	};

	window.showModalDialog = function () {
		if (debug) {
			console.info('Page secure?', location.protocol == 'https:');
			console.info('Allow insecure page?', block_mode & BLOCK_MODE.INSECURE ? false : true);
			console.info('Grant period exceeded?', Date.now() > ts + grant_period);
		}
		if (block_mode != BLOCK_MODE.ALL &&
				(block_mode & BLOCK_MODE.CONFIRM
				 ? confirmPopup('Allow modal dialog?', arguments)
				 : (block_mode & BLOCK_MODE.INSECURE ? location.protocol == 'https:' : true) && Date.now() <= ts + grant_period)) {
			console.info('Pop-Up Blocker allowed window.showModalDialog', Array.prototype.slice.apply(arguments));
			return showmodaldlg.apply(window, arguments);
		}
		else {
			console.warn('Pop-Up Blocker blocked modal showModalDialog', Array.prototype.slice.apply(arguments));
			notify('Blocked modal dialog', arguments[0], null, 0, function() {
				console.info('Pop-Up Blocker user clicked window.showModalDialog', Array.prototype.slice.apply(oargs));
				showmodaldlg.apply(window, oargs);
			});
		}
		return {}
	};

	function notify(text, uri, title, timeout, onclick, target) {
		var rootElement = document.body.parentElement,
				notification = document.createElement('div');
		if (marginTop === null) marginTop = parseFloat((rootElement.currentStyle || window.getComputedStyle(rootElement)).marginTop)
		resetStyles(notification);
		notification.style.cssText += 'background: InfoBackground !important';
		notification.style.cssText += 'border-bottom: 1px solid WindowFrame !important';
		notification.style.cssText += 'box-sizing: border-box !important';
		notification.style.cssText += 'font: small-caption !important';
		notification.style.cssText += 'padding: .15em .9em !important';
		notification.style.cssText += 'position: fixed !important';
		notification.style.cssText += 'left: 0 !important';
		notification.style.cssText += 'line-height: 2.3 !important';  // 31px
		notification.style.cssText += 'right: 0 !important';
		notification.style.cssText += 'top: -100% !important';
		notification.style.cssText += 'transition: top .25s !important';
		notification.style.cssText += 'width: 100% !important';
		notification.style.cssText += 'white-space: nowrap !important';
		notification.style.cssText += 'z-index: 2147483647 !important';
		var closeButton = document.createElement('span');
		resetStyles(closeButton);
		closeButton.style.cssText += 'cursor: pointer !important';
		closeButton.style.cssText += 'display: inline-block !important';
		closeButton.style.cssText += 'float: right !important';
		closeButton.style.cssText += 'font: inherit !important';
		closeButton.style.cssText += 'line-height: 2.1 !important';
		closeButton.style.cssText += 'margin-left: .75em !important';
		closeButton.appendChild(document.createTextNode('╳'));
		function closeNotification(event) {
			if (event) event.stopPropagation();
			//notificationOffsetTop -= notification.offsetHeight;
			if (!--notifications) rootElement.style.cssText += 'margin-top: ' + marginTop + ' !important';
			notification.style.cssText += 'top: -' + notification.offsetHeight + 'px !important';
			setTimeout(function () {
				document.body.removeChild(notification);
			}, 250);
			return false;
		}
		closeButton.onclick = closeNotification;
		notification.appendChild(closeButton);
		notification.appendChild(document.createTextNode('? ' + text));
		var numLinks = target == '_self' ? 1 : 2;
		for (var i = 0; i < numLinks; i ++) {
			var popupLink = document.createElement(!i ? 'a' : 'button');
			resetStyles(popupLink);
			if (i) {
				popupLink.style.cssText += '-moz-appearance: button !important';
				popupLink.style.cssText += '-webkit-appearance: button !important';
				popupLink.style.cssText += 'appearance: button !important';
				popupLink.style.cssText += 'font: small-caption !important';
			}
			else {
				popupLink.style.cssText += 'color: #00e !important';
				popupLink.style.cssText += 'color: -moz-nativehyperlinktext !important';
				popupLink.style.cssText += 'display: inline-block !important';
				popupLink.style.cssText += 'font: inherit !important';
				popupLink.style.cssText += 'max-width: 50% !important';
				popupLink.style.cssText += 'overflow: hidden !important';
				popupLink.style.cssText += 'text-decoration: underline !important';
				popupLink.style.cssText += 'text-overflow: ellipsis !important';
				popupLink.style.cssText += 'vertical-align: bottom !important';
				popupLink.style.cssText += 'white-space: nowrap !important';
				popupLink.setAttribute('href', uri);
				popupLink.setAttribute('target', target || '_blank');
			}
			if (title) popupLink.setAttribute('title', title);
			var linkText = i ? 'Open in this frame' : uri;
			popupLink.appendChild(document.createTextNode(linkText));
			popupLink.onclick = function(event) {
				event.stopPropagation();
				closeNotification();
				if (this.tagName.toLowerCase() != 'a') {
					location.href = uri;
				}
				else if (onclick) {
					onclick(event);
					return false;
				}
			};
			notification.appendChild(document.createTextNode(' '));
			notification.appendChild(popupLink);
		}
		if (!notifications) rootElement.style.cssText += 'transition: margin-top .25s !important';
		document.body.appendChild(notification);
		// Note: offsetHeight is zero while the element is not part of the document DOM tree
		notification.style.cssText += 'top: -' + notification.offsetHeight + 'px !important';
		setTimeout(function() {
			//notificationOffsetTop += notification.offsetHeight;
			notification.style.cssText += 'top: ' + notificationOffsetTop + 'px !important';
			if (!notifications) rootElement.style.cssText += 'margin-top: ' + (marginTop + notification.offsetHeight) + 'px !important';
			notifications ++;
		}, 0)
		if (timeout) {
			setTimeout(function () {
				closeNotification();
			}, timeout);
		}
	}

	function resetStyles(element) {
		element.style.cssText = 'background: transparent !important';
		element.style.cssText += 'border: none !important';
		element.style.cssText += 'border-radius: 0 !important';
		element.style.cssText += 'bottom: auto !important';
		element.style.cssText += 'box-shadow: none !important';
		element.style.cssText += 'color: WindowText !important';
		element.style.cssText += 'font: medium serif !important';
		element.style.cssText += 'line-height: normal !important';
		element.style.cssText += 'margin: 0 !important';
		element.style.cssText += 'opacity: 1 !important';
		element.style.cssText += 'outline: none !important';
		element.style.cssText += 'padding: 0 !important';
		element.style.cssText += 'position: static !important';
		element.style.cssText += 'text-align: left !important';
		element.style.cssText += 'text-shadow: none !important';
		element.style.cssText += 'text-transform: none !important';
		element.style.cssText += 'left: auto !important';
		element.style.cssText += 'right: auto !important';
		element.style.cssText += 'top: auto !important';
		element.style.cssText += 'white-space: normal !important';
		element.style.cssText += 'width: auto !important';
	}
})();