In this log, the problem did not occur. Button A gets clicked() normally.

"5.8.0 xcb" ()
QWidgetWindow(0x8d45438, name = "MainWindow") QTouchEvent(TouchBegin device: "eGalax Inc. eGalaxTouch EXC7200-72E1" states: TouchPointPressed, 1 points: (TouchPoint(164 (222.775,214.948 0x0) TouchPointPressed press 1 vel QVector2D(0, 0) start (222.775,214.948) last (222.775,214.948) delta (0,0)))
QWidgetWindow(0x8d45438, name = "MainWindow") QMouseEvent(MouseButtonPress, LeftButton, localPos=222.775,214.948, screenPos=222.775,214.948, MouseEventSynthesizedByQt)
QPushButton(0x8d342a8, name = "A") QMouseEvent(MouseButtonPress, LeftButton, localPos=206,115, screenPos=222.775,214.948, MouseEventSynthesizedByQt)
PRESSED "A"
QWidgetWindow(0x8d45438, name = "MainWindow") QTouchEvent(TouchUpdate device: "eGalax Inc. eGalaxTouch EXC7200-72E1" states: TouchPointPressed|TouchPointStationary, 2 points: (TouchPoint(164 (222.775,214.948 0x0) TouchPointStationary press 1 vel QVector2D(0, 0) start (222.775,214.948) last (222.775,214.948) delta (0,0), TouchPoint(165 (397.561,224.772 0x0) TouchPointPressed press 1 vel QVector2D(0, 0) start 
(397.561,224.772) last (397.561,224.772) delta (0,0)))
QWidgetWindow(0x8d45438, name = "MainWindow") QTouchEvent(TouchUpdate device: "eGalax Inc. eGalaxTouch EXC7200-72E1" states: TouchPointMoved|TouchPointStationary, 2 points: (TouchPoint(164 (222.775,214.948 0x0) TouchPointStationary press 1 vel QVector2D(0, 0) start (222.775,214.948) last (222.775,214.948) delta (0,0), TouchPoint(165 (397.171,225.24 0x0) TouchPointMoved press 1 vel QVector2D(0, 0) start (397.561,224.772) 
last (397.561,224.772) delta (-0.390152,0.467789)))
QWidgetWindow(0x8d45438, name = "MainWindow") QTouchEvent(TouchUpdate device: "eGalax Inc. eGalaxTouch EXC7200-72E1" states: TouchPointMoved|TouchPointStationary, 2 points: (TouchPoint(164 (222.775,214.948 0x0) TouchPointStationary press 1 vel QVector2D(0, 0) start (222.775,214.948) last (222.775,214.948) delta (0,0), TouchPoint(165 (397.561,225.708 0x0) TouchPointMoved press 1 vel QVector2D(0, 0) start (397.561,224.772) 
last (397.171,225.24) delta (0.390152,0.467789)))
QWidgetWindow(0x8d45438, name = "MainWindow") QTouchEvent(TouchUpdate device: "eGalax Inc. eGalaxTouch EXC7200-72E1" states: TouchPointMoved|TouchPointStationary, 2 points: (TouchPoint(164 (222.775,214.948 0x0) TouchPointStationary press 1 vel QVector2D(0, 0) start (222.775,214.948) last (222.775,214.948) delta (0,0), TouchPoint(165 (397.561,226.175 0x0) TouchPointMoved press 1 vel QVector2D(0, 0) start (397.561,224.772) 
last (397.561,225.708) delta (0,0.467789)))
QWidgetWindow(0x8d45438, name = "MainWindow") QTouchEvent(TouchUpdate device: "eGalax Inc. eGalaxTouch EXC7200-72E1" states: TouchPointMoved|TouchPointStationary, 2 points: (TouchPoint(164 (222.775,214.948 0x0) TouchPointStationary press 1 vel QVector2D(0, 0) start (222.775,214.948) last (222.775,214.948) delta (0,0), TouchPoint(165 (397.561,226.877 0x0) TouchPointMoved press 1 vel QVector2D(0, 0) start (397.561,224.772) 
last (397.561,226.175) delta (0,0.701675)))
QWidgetWindow(0x8d45438, name = "MainWindow") QTouchEvent(TouchUpdate device: "eGalax Inc. eGalaxTouch EXC7200-72E1" states: TouchPointMoved|TouchPointStationary, 2 points: (TouchPoint(164 (222.775,214.948 0x0) TouchPointStationary press 1 vel QVector2D(0, 0) start (222.775,214.948) last (222.775,214.948) delta (0,0), TouchPoint(165 (397.561,228.047 0x0) TouchPointMoved press 1 vel QVector2D(0, 0) start (397.561,224.772) 
last (397.561,226.877) delta (0,1.16948)))
QWidgetWindow(0x8d45438, name = "MainWindow") QTouchEvent(TouchUpdate device: "eGalax Inc. eGalaxTouch EXC7200-72E1" states: TouchPointStationary|TouchPointReleased, 2 points: (TouchPoint(164 (222.775,214.948 0x0) TouchPointStationary press 1 vel QVector2D(0, 0) start (222.775,214.948) last (222.775,214.948) delta (0,0), TouchPoint(165 (397.561,228.047 0x0) TouchPointReleased press 0 vel QVector2D(0, 0) start 
(397.561,224.772) last (397.561,228.047) delta (0,0)))
QWidgetWindow(0x8d45438, name = "MainWindow") QTouchEvent(TouchUpdate device: "eGalax Inc. eGalaxTouch EXC7200-72E1" states: TouchPointMoved, 1 points: (TouchPoint(164 (223.165,215.182 0x0) TouchPointMoved press 1 vel QVector2D(0, 0) start (222.775,214.948) last (222.775,214.948) delta (0.390152,0.233902)))
QWidgetWindow(0x8d45438, name = "MainWindow") QTouchEvent(TouchEnd device: "eGalax Inc. eGalaxTouch EXC7200-72E1" states: TouchPointReleased, 1 points: (TouchPoint(164 (223.165,215.182 0x0) TouchPointReleased press 0 vel QVector2D(0, 0) start (222.775,214.948) last (223.165,215.182) delta (0,0)))
QWidgetWindow(0x8d45438, name = "MainWindow") QMouseEvent(MouseButtonRelease, LeftButton, localPos=223.165,215.182, screenPos=223.165,215.182, MouseEventSynthesizedByQt)
QPushButton(0x8d342a8, name = "A") QMouseEvent(MouseButtonRelease, LeftButton, localPos=206,115, screenPos=223.165,215.182, MouseEventSynthesizedByQt)
RELEASED "A"
CLICKED "A"