Подвижная кнопка PyQt5 вызывает размытие экрана

Question

Определяемая пользователем кнопка, которая будет содержать изображение и может перемещаться, вызывает размытие экрана при перемещении влево и вызывает размытие экрана справа от виджета.Есть идеи?

Изображение размазывания справа от игральной карты - вертикальные серые линии.

Как я уже говорил, это происходит только при перемещении кнопки влево.

#!/usr/bin/python3
# -*- coding: utf-8 -*-


from PyQt5.QtCore import *
from PyQt5.QtGui import *
from PyQt5.QtWidgets import *
from functools import partial
import datetime,psutil,sys

class playingCard(QPushButton):

    def __init__(self, Text = '', parent = None):
        super(playingCard, self).__init__()
        self.ftop = 10
        self.fleft = 10
        self.fwidth = 87
        self.fheight = 124
        self.initUI()

    def initUI(self):
        self.setGeometry(self.fleft, self.ftop, self.fwidth+2, self.fheight+2)
        self.setText('')
        pixmap = QPixmap('clubs1.png')
        pixmap = pixmap.scaled(self.fwidth,self.fheight, Qt.KeepAspectRatio, Qt.FastTransformation)
        buttonicon = QIcon(pixmap)
        self.setIcon(buttonicon)
        self.setIconSize( QSize(self.fwidth,self.fheight))
        self.setFixedSize( QSize(self.fwidth+2,self.fheight+2))

    def mousePressEvent(self, event):
        self.__mousePressPos = None
        self.__mouseMovePos = None
        if event.button() == Qt.LeftButton:
            self.__mousePressPos = event.globalPos()
            self.__mouseMovePos = event.globalPos()

        super(playingCard, self).mousePressEvent(event)

    def mouseMoveEvent(self, event):
        if event.buttons() == Qt.LeftButton:
            # adjust offset from clicked point to origin of widget
            currPos = self.mapToGlobal(self.pos())
            globalPos = event.globalPos()
            diff = globalPos - self.__mouseMovePos
            newPos = self.mapFromGlobal(currPos + diff)
            self.move(newPos)

            self.__mouseMovePos = globalPos

        super(playingCard, self).mouseMoveEvent(event)

    def mouseReleaseEvent(self, event):
        if self.__mousePressPos is not None:
            moved = event.globalPos() - self.__mousePressPos 
            if moved.manhattanLength() > 3:
                event.ignore()
                return

        super(playingCard, self).mouseReleaseEvent(event)


class Example(QMainWindow):

    def __init__(self):
        super().__init__()
        self.initUI()

    def addAction(self,name,shortcut,status):
        self.actions[name] = QAction(name, self)
        self.actions[name].setShortcut(shortcut)
        self.actions[name].setStatusTip(status)
        if name == 'Exit':
            self.actions[name].triggered.connect( self.close )
        else:
            self.actions[name].triggered.connect( partial(self.viewEvent,name) )

    def hastab(self,tabname):
        return self.tabWidget.findChild(QWidget, tabname) != None

    def ontab(self,tabname):
        currentIndex = self.tabWidget.currentIndex()
        currentTitle = self.tabWidget.tabText(currentIndex)  
        return tabname == currentTitle


    def gettab(self,tabname):
        page = self.tabWidget.findChild(QWidget, tabname) 
        return self.tabWidget.indexOf(page)

    def initUI(self):               
        self.actions = dict()       # holds the QActions
        self.tabs = dict()

        self.tabWidget = QTabWidget()
        self.tabWidget.setTabsClosable(True)
        self.tabWidget.tabCloseRequested.connect(self.closeTab)
        self.setCentralWidget(self.tabWidget)

        self.addAction('Exit', 'Ctrl+Q','Exit application')
        self.addAction('Game','Ctrl+G','Game')

        self.statusBar()

        menubar = self.menuBar()
        fileMenu = menubar.addMenu('&File')

        fileMenu.addAction( self.actions['Game'] )
        fileMenu.addAction( self.actions['Exit'] )

        self.setWindowTitle('Main window')
        self.showMaximized()

    def closeTab (self, currentIndex):
        currentQWidget = self.tabWidget.widget(currentIndex)
        title=self.tabWidget.tabText(currentIndex)
        currentQWidget.deleteLater()
        self.tabWidget.removeTab(currentIndex)

        del self.tabs[title]
        del self.tables[title]
        self.timers[title].stop()
        del self.timers[title]

    def keyPressEvent(self, e):  

        currentIndex=self.tabWidget.currentIndex()
        title = None
        if currentIndex != -1:
            title=self.tabWidget.tabText(currentIndex)

        if e.key() == Qt.Key_F11:
            if self.isMaximized():
                self.showNormal()
            else:
                self.showMaximized()

    def viewEvent(self, name):
        if name in self.tabs:
            return

        self.tabs[name] = QWidget()

        vbox = QVBoxLayout()
        vbox.addWidget( playingCard() )


        # Add box layout, add table to box layout and add box layout to widget
        self.tabs[name].layout = vbox
        self.tabs[name].setLayout(self.tabs[name].layout) 
        self.tabWidget.addTab(self.tabs[name],name)

    def closeEvent(self, event):

        reply = QMessageBox.question(self, 'Message',
            "Are you sure to quit?", QMessageBox.Yes | 
            QMessageBox.No, QMessageBox.No)

        if reply == QMessageBox.Yes:
            event.accept()
        else:
            event.ignore()  

if __name__ == '__main__':

    app = QApplication(sys.argv)
    ex = Example()
    sys.exit(app.exec_())