Greasy Fork is available in English.
http://hackforums.net/showthread.php?tid=5207086
// ==UserScript==
// @name CTRL+S Shortcut
// @namespace Shortcut
// @description http://hackforums.net/showthread.php?tid=5207086
// @include *hackforums.net/showthread.php?tid=*
// @require http://ajax.googleapis.com/ajax/libs/jquery/2.1.4/jquery.min.js
// @version 0.2
// @grant GM_getValue
// ==/UserScript==
$(document).on("keydown", function(e){
if (e.ctrlKey && e.which === 83) {
if ($("#message").val() === "") {
$(document).scrollTop(10000);
$("#message").focus();
} else {
$("#quick_reply_submit").click();
}
e.preventDefault();
return false;
}
});