Screen, root= 4b4 "5.10.0 xcb" () destroy QWidgetWindow(0x1e4c2c0, name="TopLevelWindow") m_window 0 create QWidgetWindow(0x1e4c2c0, name="TopLevelWindow") m_window 5800005 destroy QWidgetWindow(0x1f7b730, name="QMessageBoxClassWindow") m_window 0 create QWidgetWindow(0x1f7b730, name="QMessageBoxClassWindow") m_window 580000d Xcb_translate_coordinates src_window= 580000d QWidgetWindow(0x1f7b730, name="QMessageBoxClassWindow") dst_window= 4b4 QWindow(0x0) x,y 0 0 Xcb_translate_coordinates src_window= 3200271 QWindow(0x0) dst_window= 3200270 QWindow(0x0) x,y 0 0 hide >look topLevelAt QPoint(930,554) root= 4b4 # 0 loop parent 4b4 child= 4b4 Xcb_translate_coordinates Xcb_translate_coordinates_unchecked src_window= 4b4 QWindow(0x0) dst_window= 4b4 QWindow(0x0) x,y 930 554 xcb_translate_coordinates_reply_t( response_type 1 same_screen= 1 child= 3200270 x,y 930 554 ) # 1 loop parent 4b4 child= 3200270 Xcb_translate_coordinates >>>> QXcbScreen::topLevelAt() hits on message box frame in the process of being destroyed Xcb_translate_coordinates_unchecked src_window= 4b4 QWindow(0x0) dst_window= 3200270 QWindow(0x0) x,y 930 554 xcb_translate_coordinates_reply_t( 0 ) 0 reply hide