In my system, decimal separator is comma. In transaction list in a GUI for all mounts decimal separator is point. But in amount filter field I can't enter point, only comma (which is decimal separator in my system), and, most likely because of that, filtering by amount does not work.

It's bitcoin-qt v0.16.0 with qt 5.9.4 on Gentoo Linux.

![image](https://user-images.githubusercontent.com/4500994/43676682-635500c6-97fe-11e8-9f14-490ecdce4adc.png)

dateWidget->addItem(tr("All"), All);
    dateWidget->addItem(tr("Today"), Today);
    dateWidget->addItem(tr("This week"), ThisWeek);
    dateWidget->addItem(tr("This month"), ThisMonth);
    dateWidget->addItem(tr("Last month"), LastMonth);
    dateWidget->addItem(tr("This year"), ThisYear);
    dateWidget->addItem(tr("Range..."), Range);
    hlayout->addWidget(dateWidget);
    typeWidget = new QComboBox(this);
    if (platformStyle->getUseExtraSpacing()) {
        typeWidget->setFixedWidth(121);
    } else {
        typeWidget->setFixedWidth(120);
    }
    typeWidget->addItem(tr("All"), TransactionFilterProxy::ALL_TYPES);
    typeWidget->addItem(tr("Received with"), TransactionFilterProxy::TYPE(TransactionRecord::RecvWithAddress) |
                                        TransactionFilterProxy::TYPE(TransactionRecord::RecvFromOther));
    typeWidget->addItem(tr("Sent to"), TransactionFilterProxy::TYPE(TransactionRecord::SendToAddress) |
                                  TransactionFilterProxy::TYPE(TransactionRecord::SendToOther));
    typeWidget->addItem(tr("To yourself"), TransactionFilterProxy::TYPE(TransactionRecord::SendToSelf));
    typeWidget->addItem(tr("Mined"), TransactionFilterProxy::TYPE(TransactionRecord::Generated));
    typeWidget->addItem(tr("Other"), TransactionFilterProxy::TYPE(TransactionRecord::Other));
    hlayout->addWidget(typeWidget);
    search_widget = new QLineEdit(this);
    search_widget->setPlaceholderText(tr("Enter address, transaction id, or label to search"));
    hlayout->addWidget(search_widget);
    amountWidget = new QLineEdit(this);
    amountWidget->setPlaceholderText(tr("Min amount"));
    if (platformStyle->getUseExtraSpacing()) {
        amountWidget->setFixedWidth(97);