Untitled

// ==UserScript==
// @name           4chan jp flags
// @version        1.0
// @description    There really needs to be flags on /jp/, like on /int/.
// @include        http://boards.4chan.org/jp/*
// @run-at         document-end
// ==/UserScript==

function flag() {
  var e = document.createElement("img");
  e.src = "//static.4chan.org/image/country/jp.gif";
  e.className = "countryFlag";
  return e;
}

var names = document.getElementsByClassName("nameBlock");
for (var i=0; i<names.length; i++) {
  names[i].firstChild.innerHTML += " ";
  names[i].insertBefore(flag(), names[i].firstChild.nextSibling);
}