Invert colors in Chrome Browser (with DevTools JavaScript console)

gistfile1.js

javascript: (function () {
  // the css we are going to inject
  var css =
      "html {" +
      "    -webkit-filter: invert(100%);" +
      "    -moz-filter:    invert(100%);" +
      "    -o-filter:      invert(100%);" +
      "    -ms-filter:     invert(100%);" +
      "}",
    head = document.getElementsByTagName("head")[0],
    style = document.createElement("style");

  // a hack, so you can "invert back" clicking the bookmarklet again
  if (!window.counter) {
    window.counter = 1;
  } else {
    window.counter++;
    if (window.counter % 2 == 0) {
      // showing another way instead of multiple strings with + you can use \
      var css =
        "html { \
            -webkit-filter: invert(0%); \
            -moz-filter:    invert(0%); \
            -o-filter:      invert(0%); \
            -ms-filter:     invert(0%); \
        }";
    }
  }

  style.type = "text/css";
  if (style.styleSheet) {
    style.styleSheet.cssText = css;
  } else {
    style.appendChild(document.createTextNode(css));
  }

  //injecting the css to the head
  head.appendChild(style);
})();

Bookmarklets tend to be one line of code. If you add them to a bookmark, replacing the url of a bookmark for anything, they replace things like spaces with the %.... and similar.

This is very cool. Thank you.