--- a/s4-main.js	Mon Nov 08 18:16:33 2021 +0900
+++ b/s4-main.js	Mon Nov 08 18:17:18 2021 +0900
@@ -975,6 +975,14 @@
 	let ta = document.querySelector("textarea");
 	if (!ta) return;
 	let btn = document.createElement("button");
+	btn.setAttribute("title", "\\( と \\) で数式利用\n"+
+			 "\\[ と \\] で段組み数式モード\n"+
+			 "便利なマクロ:\n"+
+			 " \\boxed{aaa}, \\fcolorbox{framecolor}{bgcolor}{text}\n"+
+			 " \\underline{aaa}, \\fcolorbox{framecolor}{bgcolor}{text}\n"+
+			 "独自定義マクロ:\n"+
+			 " \\warn{xxx}  注意喚起用色付き枠\n"+
+			 " \\Warn{xxx}  大きな文字で注意喚起")
 	btn.innerHTML = "MathJax<br>Preview";
 	btn.addEventListener('click', (e) => {
 	    e.preventDefault();