nicovideo-thumbnail-display.user.js

// ==UserScript==
// @name           display nicovideo movie thumbnail on watch page
// @namespace      http://uu59.org/
// @version        1.0.0
// @include        http://www.nicovideo.jp/watch/*
// ==/UserScript==

(function(){
  var addCss = function(css){
    var head = document.querySelector("head")
    var style = document.createElement("style");
    head.appendChild(style);
    style.type = "text/css";
    style.appendChild(document.createTextNode(css));
  }
  var id = document.querySelector('link[rel="canonical"]').href.match(/sm([0-9]+)/)
  if(!id) return;
  var id = id[1];
  var thumburl = "http://tn-skr.smilevideo.jp/smile?i="+id;
  var info = document.getElementById("itab_description");
  addCss('#itab_description:after {' +
    'content: ""; display: block; clear:both;' +
    '}'
  );
  info.innerHTML = '<p style="float:right;"><img src="'+thumburl+'" /></p>'+
    info.innerHTML
  ;
    
  ;
})();