add autoheight for textarea (again)

autosize.js

@@ -0,0 +1,10 @@
+function autosize(tx) {
+  for (let i = 0; i < tx.length; i++) {
+    tx[i].setAttribute("style", "height:" + (tx[i].scrollHeight) + "px;overflow-y:hidden;");
+    tx[i].addEventListener("input", OnInputAutoSize, false);
+  }
+}
+function OnInputAutoSize() {
+  this.style.height = "auto";
+  this.style.height = (this.scrollHeight) + "px";
+}