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)

mapperThirdPartyTxUrls = new QSignalMapper(this);
    
    connect(mapperThirdPartyTxUrls, static_cast<void (QSignalMapper::*)(const QString&)>(&QSignalMapper::mapped), this, &TransactionView::openThirdPartyTxUrl);
    connect(dateWidget, static_cast<void (QComboBox::*)(int)>(&QComboBox::activated), this, &TransactionView::chooseDate);
    connect(typeWidget, static_cast<void (QComboBox::*)(int)>(&QComboBox::activated), this, &TransactionView::chooseType);
    connect(watchOnlyWidget, static_cast<void (QComboBox::*)(int)>(&QComboBox::activated), this, &TransactionView::chooseWatchonly);
    connect(amountWidget, &QLineEdit::textChanged, amount_typing_delay, static_cast<void (QTimer::*)()>(&QTimer::start));
    connect(amount_typing_delay, &QTimer::timeout, this, &TransactionView::changedAmount);
    connect(search_widget, &QLineEdit::textChanged, prefix_typing_delay, static_cast<void (QTimer::*)()>(&QTimer::start));
    connect(prefix_typing_delay, &QTimer::timeout, this, &TransactionView::changedSearch);
    connect(view, &QTableView::doubleClicked, this, &TransactionView::doubleClicked);
    connect(view, &QTableView::customContextMenuRequested, this, &TransactionView::contextualMenu);
    connect(bumpFeeAction, &QAction::triggered, this, &TransactionView::bumpFee);
    connect(abandonAction, &QAction::triggered, this, &TransactionView::abandonTx);
    connect(copyAddressAction, &QAction::triggered, this, &TransactionView::copyAddress);
    connect(copyLabelAction, &QAction::triggered, this, &TransactionView::copyLabel);
    connect(copyAmountAction, &QAction::triggered, this, &TransactionView::copyAmount);
    connect(copyTxIDAction, &QAction::triggered, this, &TransactionView::copyTxID);
    connect(copyTxHexAction, &QAction::triggered, this, &TransactionView::copyTxHex);
    connect(copyTxPlainText, &QAction::triggered, this, &TransactionView::copyTxPlainText);
    connect(editLabelAction, &QAction::triggered, this, &TransactionView::editLabel);
    connect(showDetailsAction, &QAction::triggered, this, &TransactionView::showDetails);
    
    connect(this, &TransactionView::doubleClicked, this, &TransactionView::showDetails);
    
    connect(this, &TransactionView::bumpedFee, [this](const uint256& txid) {
      focusTransaction(txid);
    });
}
void TransactionView::setModel(WalletModel *_model)