_Second try - first issue got deleted suddenly..._

When confirming too big transactions, depending on screen resolution with each output the buttons move lower and lower until they are not visible anymore on the screen.

Additionally randomly after a couple transactions the client starts to repeat its content in the confirmation prompt making even the smalest 1:1 transaction unusable as the buttons are not visible, again. (See screenshot)

I (A) would expect that the buttons are visible no matter how big the transaction content is (for example by making the content scrollable) and (B) don't understand why the content is repeating suddenly.

Using Bitcoin Knots 17 but have been directed by the developers that the issue belongs to bitcoin/bitcoin

![bug-NEW](https://user-images.githubusercontent.com/48955884/55005357-2396de00-4fdc-11e9-9c6c-2b869777e64e.png)

Windows 10
1920x1080
Intel i7
class PlatformStyle;
class SendCoinsEntry;
class SendCoinsRecipient;
namespace Ui {
    class SendCoinsDialog;
}
QT_BEGIN_NAMESPACE
class QUrl;
QT_END_NAMESPACE
class SendCoinsDialog : public QDialog
{
    Q_OBJECT
public:
    explicit SendCoinsDialog(const PlatformStyle *platformStyle, QWidget *parent = nullptr);
    ~SendCoinsDialog();
    void setClientModel(ClientModel *clientModel);
    void setModel(WalletModel *model);
    /** Set up the tab chain manually, as Qt messes up the tab chain by default in some cases (issue https://bugreports.qt-project.org/browse/QTBUG-10907).
     */
    QWidget *setupTabChain(QWidget *prev);
    void setAddress(const QString &address);
    void pasteEntry(const SendCoinsRecipient &rv);
    bool handlePaymentRequest(const SendCoinsRecipient &recipient);
public Q_SLOTS:
    void clear();
    void reject();
    void accept();
    SendCoinsEntry *addEntry();
    void updateTabsAndLabels();