qt tx dialog: fix visual artifact when opening (widget parenting issue)

electrum/gui/qt/locktimeedit.py

@@ -27,9 +27,9 @@ class LockTimeEdit(QWidget):
         hbox.setContentsMargins(0, 0, 0, 0)
         hbox.setSpacing(0)
 
-        self.locktime_raw_e = LockTimeRawEdit()
+        self.locktime_raw_e = LockTimeRawEdit(self)
-        self.locktime_height_e = LockTimeHeightEdit()
+        self.locktime_height_e = LockTimeHeightEdit(self)
-        self.locktime_date_e = LockTimeDateEdit()
+        self.locktime_date_e = LockTimeDateEdit(self)
         self.editors = [self.locktime_raw_e, self.locktime_height_e, self.locktime_date_e]
 
         self.combo = QComboBox()

electrum/gui/qt/transaction_dialog.py

@@ -640,7 +640,7 @@ class BaseTxDialog(QDialog, MessageBoxMixin):
         locktime_setter_hbox.setSpacing(0)
         locktime_setter_label = TxDetailLabel()
         locktime_setter_label.setText("LockTime: ")
-        self.locktime_e = LockTimeEdit()
+        self.locktime_e = LockTimeEdit(self)
         locktime_setter_hbox.addWidget(locktime_setter_label)
         locktime_setter_hbox.addWidget(self.locktime_e)
         locktime_setter_hbox.addStretch(1)