Block internal images hardcoded in IMG tag

Remove about: chrome: and resource: URIs from the src attribute of <img> tags.

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        Block internal images hardcoded in IMG tag
// @description Remove about: chrome: and resource: URIs from the src attribute of <img> tags.
// @author      Jefferson "jscher2000" Scher
// @namespace   JeffersonScher
// @copyright   Copyright 2016 Jefferson Scher
// @license     BSD 3-clause
// @include     http*://*
// @version     0.5.1
// @grant       none
// ==/UserScript==

// Inspiration -- also deals with <script> tags: http://userscripts-mirror.org/scripts/review/5899

// Check <img> tags for about: chrome: resource: URLs
var problemimgs = document.querySelectorAll('img[src^="about:"], img[src^="chrome:"], img[src^="resource:"]');
for(var i = 0; i < problemimgs.length; i++){
  if (problemimgs[i].hasAttribute("onload")) problemimgs[i].removeAttribute("onload");
  if (problemimgs[i].hasAttribute("onerror")) problemimgs[i].removeAttribute("onerror");
  problemimgs[i].setAttribute("alt", "BLOCKED: "+problemimgs[i].getAttribute("src"));
  problemimgs[i].removeAttribute("src");
  problemimgs[i].setAttribute("style", "border:3px double red; color:red; font-weight:bold; font-style:italic; padding: 1px 4px;");
}