gistfile1.js

// ==UserScript==
// @name           portal corse list
// @namespace      portal
// @include        https://portal.yzu.edu.tw/VC2/Student/classLeft_S.aspx
// ==/UserScript==

var sw = GM_getValue("switch", null) || "on";

if(sw == "on") {
    document.body.innerHTML = document.body.innerHTML.replace(
        /(課程名稱【(\W+)[A-Z] ?班】[^>]*>)[^<]+<\/a>/g, "$1$2</a>"
    );
}

var link = document.createElement("a");
link.href = "#";
link.textContent = "switch: " + sw;
link.className = "left_menu";

link.addEventListener("click", function(e) {
    sw = sw == "on" ? "off" : "on";
    GM_setValue("switch", sw);
    location.reload();
}, false);

var menu = document.getElementsByClassName("menu")[0];
var thead = menu.createTHead();
thead.align = "center";
thead.appendChild(link);