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
{
    overviewAction->setChecked(true);
    if (walletFrame) walletFrame->gotoOverviewPage();
}
void BitcoinGUI::gotoHistoryPage()
{
    historyAction->setChecked(true);
    if (walletFrame) walletFrame->gotoHistoryPage();
}
void BitcoinGUI::gotoReceiveCoinsPage()
{
    receiveCoinsAction->setChecked(true);
    if (walletFrame) walletFrame->gotoReceiveCoinsPage();
}
void BitcoinGUI::gotoSendCoinsPage(QString addr)
{
    sendCoinsAction->setChecked(true);
    if (walletFrame) walletFrame->gotoSendCoinsPage(addr);
}
void BitcoinGUI::gotoSignMessageTab(QString addr)
{
    if (walletFrame) walletFrame->gotoSignMessageTab(addr);
}
void BitcoinGUI::gotoVerifyMessageTab(QString addr)