spoiler-killer.js

// ==UserScript==
// @name           Spoiler Killer
// @include        http://*.facebook.com/*
// @include        https://*.facebook.com/*
// @require        http://code.jquery.com/jquery-1.7.1.min.js
// @require        https://gist.github.com/raw/2625891/waitForKeyElements.js
// @grant          none
// @version 1
// @namespace http://shivamverma.info
// @description Blacken facebook posts possibly containing Game of Thrones spoilers. 
// ==/UserScript==

(function(){
	var spoiler = 'I am a dumbass ! (<i>via Spoiler Killer</i>)';
	var terms = ['spoiler', 'game of thrones', 'hodor', 'jon snow', 'khaleesi', 'stark', 'dothraki'];
	function actionFunction(node){
	    var content = node.html();
	    content = content.toLowerCase();
	    $.each(terms, function(index, term){
	        if(content.indexOf(term) > -1){
                var overlay = $('<div />' ).css({
                     position: "absolute",
                     width: "100%",
                     height: "100%",
                     left: 0,
                     top: 0,
                     zIndex: 1000000,
                     background: "#000000",
                 });
                (function(overlay, node){
                    overlay.appendTo(node.css("position", "relative"));
                    $(node).on("mouseenter", function(){
	                    overlay.hide();
	                });
	                $(node).on("mouseleave", function(){
	                    overlay.show();
	                });
                })(overlay, node);
	        }
	    });
	}
	waitForKeyElements("div.userContentWrapper", actionFunction);
})();