The part of the GUI that this setting is relevant for does not exist in a `--disable-wallet` build. 

![wallet_prefs](https://user-images.githubusercontent.com/863730/70331435-72547300-180d-11ea-842d-82f8529ae982.png)
connect(ui->prune, &QCheckBox::clicked, this, &OptionsDialog::showRestartWarning);
    connect(ui->prune, &QCheckBox::clicked, this, &OptionsDialog::togglePruneWarning);
    connect(ui->pruneSize, static_cast<void (QSpinBox::*)(int)>(&QSpinBox::valueChanged), this, &OptionsDialog::showRestartWarning);
    connect(ui->databaseCache, static_cast<void (QSpinBox::*)(int)>(&QSpinBox::valueChanged), this, &OptionsDialog::showRestartWarning);
    connect(ui->threadsScriptVerif, static_cast<void (QSpinBox::*)(int)>(&QSpinBox::valueChanged), this, &OptionsDialog::showRestartWarning);
    
    connect(ui->spendZeroConfChange, &QCheckBox::clicked, this, &OptionsDialog::showRestartWarning);
    
    connect(ui->allowIncoming, &QCheckBox::clicked, this, &OptionsDialog::showRestartWarning);
    connect(ui->connectSocks, &QCheckBox::clicked, this, &OptionsDialog::showRestartWarning);
    connect(ui->connectSocksTor, &QCheckBox::clicked, this, &OptionsDialog::showRestartWarning);
    
    connect(ui->lang, static_cast<void (QValueComboBox::*)()>(&QValueComboBox::valueChanged), [this]{ showRestartWarning(); });
    connect(ui->thirdPartyTxUrls, &QLineEdit::textChanged, [this]{ showRestartWarning(); });
}
void OptionsDialog::setCurrentTab(OptionsDialog::Tab tab)
{
    QWidget *tab_widget = nullptr;
    if (tab == OptionsDialog::Tab::TAB_NETWORK) tab_widget = ui->tabNetwork;
    if (tab == OptionsDialog::Tab::TAB_MAIN) tab_widget = ui->tabMain;
    if (tab_widget && ui->tabWidget->currentWidget() != tab_widget) {
        ui->tabWidget->setCurrentWidget(tab_widget);
    }
}
void OptionsDialog::setMapper()
{
    
    mapper->addMapping(ui->bitcoinAtStartup, OptionsModel::StartAtStartup);