WIP essentials 10

messages_essentials.go

@@ -26,6 +26,8 @@ func init() {
 		"signature_pad.empty": {"Sign here", "请在此签名"},
 		"signature_pad.clear": {"Clear", "清除"},
 
+		"undo_toast.undo": {"Undo", "撤销"},
+
 		"qr_code.label":    {"QR code", "二维码"},
 		"qr_code.too_long": {"Text too long for a QR code", "文字过长，无法生成二维码"},
 	})