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)

{
    if(!transactionProxyModel)
        return;
    transactionProxyModel->setWatchOnlyFilter(
        static_cast<TransactionFilterProxy::WatchOnlyFilter>(watchOnlyWidget->itemData(idx).toInt()));
}
void TransactionView::changedSearch()
{
    if(!transactionProxyModel)
        return;
    transactionProxyModel->setSearchString(search_widget->text());
}
void TransactionView::changedAmount()
{
    if(!transactionProxyModel)
        return;
    CAmount amount_parsed = 0;
    if (BitcoinUnits::parse(model->getOptionsModel()->getDisplayUnit(), amountWidget->text(), &amount_parsed)) {
        transactionProxyModel->setMinAmount(amount_parsed);
    }
    else
    {
        transactionProxyModel->setMinAmount(0);
    }
}
void TransactionView::exportClicked()
{
    if (!model || !model->getOptionsModel()) {