Hide Facebook News feed entries which are random posts from friends' liked pages. They are matched by looking for the 'Like Page' button within a news feed entry. Instructions for adding user scripts to Chrome here: http://stackoverflow.com/questions/5258989/manually-adding-a-userscript-to-google-chrome or for Firefox use Greasemonkey. It's prob…

Hide_Facebook_Like_News.user.js

// ==UserScript==
// @name        Hide Facebook 'Like' News
// @namespace   uk.me.amoss
// @include     /https?://www.facebook.com/.*/
// @version     1
// @grant       none
// ==/UserScript==

// Configurable
var indicateInsteadOfHiding = false;

var newsItemAddedObserver = null;

window.onload = function() {
	if( newsItemAddedObserver !== null ) {
		return;
	}

	var newsDivSelection = document.evaluate('//div[starts-with(@id, "topnews_main_stream")]', document, null, XPathResult.ORDERED_NODE_SNAPSHOT_TYPE, null);
	if( newsDivSelection.snapshotLength === 0 ) {
		console.log('No news stream div found.');
	} else if( newsDivSelection.snapshotLength > 1 ) {
		console.log('Multiple news stream divs found.');
	} else {
		newsItemAddedObserver = new MutationObserver(function(mutations) {
			mutations.forEach(function(mutation) {
				for( var i = 0; i < mutation.addedNodes.length; i++ ) {
					var addedNode = mutation.addedNodes[i];
					if( addedNode.id.indexOf('jsonp') > -1 ) {
						hideMatchingDivs(addedNode);
					}
				}
			});
		});
		newsItemAddedObserver.observe(newsDivSelection.snapshotItem(0), { subtree: true, childList: true });
		hideMatchingDivs(document);
	}

	function hideMatchingDivs(element) {
		var spamDivs = document.evaluate('//div[contains(@id, "jsonp") and .//button[contains(text(), "Like Page")]]', element, null, XPathResult.ORDERED_NODE_SNAPSHOT_TYPE, null);
		console.log('Detected ' + spamDivs.snapshotLength + ' matching divs.');
		for( var i = 0; i < spamDivs.snapshotLength; i++ ) {
			if( indicateInsteadOfHiding ) {
				spamDivs.snapshotItem(i).style.border = '3px solid red';
			} else {
				spamDivs.snapshotItem(i).style.display = 'none';
			}
		}
	}
};