Block/Hide Facebook elements (and do something useful with that time of yours instead!)

fb-blocker.user.js

// ==UserScript==
// @name        Facebook Blocker (by Jouni Kaplas)
// @namespace   net.kaplas.fb-blocker
// @include     https://*.facebook.com/*
// @include     https://facebook.com/*
// @include     http://*.facebook.com/*
// @include     http://facebook.com/*
// @version     1
// @grant       none
// @downloadURL https://gist.github.com/kaplas/31cf00f605667f7430d9/raw/
// @description Block/Hide Facebook elements
// ==/UserScript==

var HIDE_THESE = [
  ".home #contentArea",         // newsfeed
  "#pagelet_ego_pane",          // suggested pages
  "#timeline_info_review_unit"  // add this and that to your profile
]

var styleNode = document.createElement('style');

var rules = [];
function addStyleRule(selector, attribute, value) {
  rules.push(`${selector} { ${attribute}: ${value} !important }`);
}

// This doesn't hide the actual element, but it's child elements instead.
function hideElementsBySelector(selector) {
  var childSelector = `${selector} *`;
  addStyleRule(selector, "background-color", "silver");
  addStyleRule(childSelector, "visibility", "hidden");
}

HIDE_THESE.forEach(hideElementsBySelector);
styleNode.innerHTML = rules.join("\n");
document.body.appendChild(styleNode);