If the main window has been minimized to the taskbar (iconified) calling "Show/Hide", "Send" or "Receive" actions from the tray icon menu has no effect: the main window still minimized.

It seems like a Qt bug similar to that old [one](https://bugreports.qt.io/browse/QTBUG-31117).

Tested platform: Linux Mint 19, Qt 5.9.5 / 5.9.6
#ifndef BITCOIN_QT_BITCOINGUI_H
#define BITCOIN_QT_BITCOINGUI_H
#if defined(HAVE_CONFIG_H)
#include <config/bitcoin-config.h>
#endif
#include <qt/optionsdialog.h>
#include <amount.h>
#include <QLabel>
#include <QMainWindow>
#include <QMap>
#include <QMenu>
#include <QPoint>
#include <QSystemTrayIcon>
#ifdef Q_OS_MAC
#include <qt/macos_appnap.h>
#endif
#include <memory>
class ClientModel;