Image Background Color

Sets a checkerboard (or color) background on images viewed standalone.

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        Image Background Color
// @namespace   leaumar
// @match       *://*/*
// @grant       none
// @version     2
// @author      [email protected]
// @description Sets a checkerboard (or color) background on images viewed standalone.
// @license     MPL-2.0
// @icon        data:image/png;base64,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
// ==/UserScript==

const checkerBoard = {
  backgroundColor: 'darkgrey',
  backgroundImage: 'linear-gradient(45deg, grey 25%, transparent 25%, transparent 75%, grey 75%, grey), linear-gradient(45deg, grey 25%, transparent 25%, transparent 75%, grey 75%, grey)',
  backgroundPosition: '0 0, 2vmin 2vmin',
  backgroundSize: '4vmin 4vmin',
};

function setBackground(node) {
  Object.assign(node.style, checkerBoard);
  // or assign a fixed color if you want
  // node.style.backgroundColor = '#333';
}

function getStandaloneImage() {
  const tags = [...document.body.childNodes]
    .filter(node => node.nodeName !== '#text');

  return tags.length === 1 && tags[0].nodeName === 'IMG' ? tags[0] : null;
}

function clearAllBackgrounds(upFrom) {
  let current = upFrom;
  while (current?.style != null) {
    current.style.background = 'unset';
    current = current.parentNode;
  }
}

(function main() {
  const img = getStandaloneImage();
  if (img != null) {
    clearAllBackgrounds(img);
    setBackground(document.body);
  }
})();