Periodically removes sponsored content from the Facebook news feed.

remove-facebook-ads.js

// ==UserScript==
// @name         Remove Facebook Ads
// @version      1.0
// @description  Removes sponsored content from the Facebook news feed.
// @author       theftprevention
// @match        https://www.facebook.com/
// @grant        none
// ==/UserScript==

(function() {
    'use strict';

    var interval = 1000;
    var reg_sponsored = /^Sponsored$/i;
    var rightColumnPageletSelector = ".home_right_column .pagelet-group:not(#stories_pagelet_rhc):not(#pagelet_reminders)";
    var subtitleSelector = "[data-testid='story-subtitle'] > span:first-child";
    var titleSelector = "a[href][data-hovercard]:not([tabindex='-1'])";
    var whitelist = new WeakSet();

    /**
     * @returns {Array<HTMLElement>}
     */
    function findAds() {
        var a = 0;
        var ads = [];
        var i, l;

        var element;
        var subtitle;
        var subtitles = document.querySelectorAll(subtitleSelector);

        // 1. Sponsored news feed stories
        for (i = 0, l = subtitles.length; i < l; i++) {
            subtitle = subtitles[i];
            if (whitelist.has(subtitle)) {
                continue;
            }
            whitelist.add(subtitle);
            element = getParentStoryElement(subtitle);
            if (!element || whitelist.has(element)) {
                continue;
            }
            if (reg_sponsored.test(getDisplayedInnerText(subtitle))) {
                ads[a++] = element;
            } else {
                whitelist.add(element);
            }
        }

        // 2. Right column pagelet advertisements
        var pagelets = document.querySelectorAll(rightColumnPageletSelector);
        for (i = 0, l = pagelets.length; i < l; i++) {
            ads[a++] = pagelets[i];
        }

        return ads;
    }

    /**
     * @param {HTMLElement} element
     * @returns {string}
     */
    function getDisplayedInnerText(element) {
        var style = getComputedStyle(element);
        if (style.display === 'none') {
            return '';
        }
        var child;
        var children = element.childNodes;
        var text = '';
        for (var i = 0, l = children.length; i < l; i++) {
            child = children[i];
            switch (child.nodeType) {
                case Node.ELEMENT_NODE:
                    text += getDisplayedInnerText(child);
                    break;
                case Node.TEXT_NODE:
                    text += child.textContent;
                    break;
            }
        }
        return text;
    }

    /**
     * @param {ChildNode} node
     * @returns {HTMLElement | undefined}
     */
    function getParentStoryElement(node) {
        var element = node.parentElement;
        while (element && element !== document.body) {
            if (element.getAttribute('data-testid') === 'fbfeed_story') {
                return element;
            }
            element = element.parentElement;
        }
    }

    /**
     * @returns {Array<HTMLElement>}
     */
    function removeAds() {
        var ad;
        var ads = findAds();
        var count = ads.length;
        var i = count;
        var parent;
        var title;
        var titleElement;
        while (i--) {
            ad = ads[i];
            parent = ad.parentNode;
            if (parent) {
                titleElement = ad.getAttribute('data-testid') === 'fbfeed_story' ? ad.querySelector(titleSelector) : null;
                title = titleElement ? titleElement.textContent.trim() : '';
                try {
                    parent.removeChild(ad);
                    if (title) {
                        console.log('Removed an advertisement from %c' + title + '%c.', 'font-weight: bold', '');
                    }
                } catch (e) {
                    if (e instanceof Error) {
                        if (title) {
                            console.error('Failed to remove an advertisement from %c' + title + '%c: (' + e.name + ') ' + e.message, 'font-weight: bold', '');
                        } else {
                            console.error('Failed to remove an advertisement: (' + e.name + ') ' + e.message);
                        }
                    }
                }
            }
        }
        return ads;
    }

    /**
     * @returns {void}
     */
    function initialize() {
        document.removeEventListener('DOMContentLoaded', initialize);
        setInterval(removeAds, interval);
    }

    if (document.readyState === 'loading') {
        document.addEventListener('DOMContentLoaded', initialize);
    } else {
        initialize();
    }

})();