Set the RBF flat to all transactions, and remove the 'use_rbf'

preference from the GUI, because the mempoolfullrbf option in
Bitcoin 0.24 makes RBF signaling pretty meaningless. Fixes #8088.

Note: RBF remains disabled for channel funding transactions.
In that case, the flag is actually only used as a semaphore
between different instances of the same wallet.

electrum/gui/kivy/uix/dialogs/confirm_tx_dialog.py

@@ -26,7 +26,6 @@ Builder.load_string('''
     message: ''
     warning: ''
     extra_fee: ''
-    show_final: False
     size_hint: 0.8, 0.8
     pos_hint: {'top':0.9}
     method: 0
@@ -82,17 +81,6 @@ Builder.load_string('''
             range: 0, 4
             step: 1
             on_value: root.on_slider(self.value)
-        BoxLayout:
-            orientation: 'horizontal'
-            size_hint: 1, 0.2
-            Label:
-                text: _('Final')
-                opacity: int(root.show_final)
-            CheckBox:
-                id: final_cb
-                opacity: int(root.show_final)
-                disabled: not root.show_final
-                on_release: root.update_tx()
         Label:
             text: root.warning
             text_size: self.width, None
@@ -122,7 +110,7 @@ Builder.load_string('''
 
 class ConfirmTxDialog(FeeSliderDialog, Factory.Popup):
 
-    def __init__(self, app: 'ElectrumWindow', amount, make_tx, on_pay, *, show_final=True):
+    def __init__(self, app: 'ElectrumWindow', amount, make_tx, on_pay):
 
         Factory.Popup.__init__(self)
         FeeSliderDialog.__init__(self, app.electrum_config, self.ids.slider)
@@ -130,16 +118,14 @@ class ConfirmTxDialog(FeeSliderDialog, Factory.Popup):
         self.amount = amount
         self.make_tx = make_tx
         self.on_pay = on_pay
-        self.show_final = show_final
         self.update_slider()
         self.update_text()
         self.update_tx()
 
     def update_tx(self):
-        rbf = not bool(self.ids.final_cb.active) if self.show_final else False
         try:
             # make unsigned transaction
-            tx = self.make_tx(rbf)
+            tx = self.make_tx()
         except NotEnoughFunds:
             self.warning = _("Not enough funds")
             self.ids.ok_button.disabled = True

electrum/gui/kivy/uix/screens.py

@@ -438,7 +438,7 @@ class SendScreen(CScreen, Logger):
         outputs = invoice.outputs
         amount = sum(map(lambda x: x.value, outputs)) if not any(parse_max_spend(x.value) for x in outputs) else '!'
         coins = self.app.wallet.get_spendable_coins(None)
-        make_tx = lambda rbf: self.app.wallet.make_unsigned_transaction(coins=coins, outputs=outputs, rbf=rbf)
+        make_tx = lambda: self.app.wallet.make_unsigned_transaction(coins=coins, outputs=outputs)
         on_pay = lambda tx: self.app.protected(_('Send payment?'), self.send_tx, (tx, invoice))
         d = ConfirmTxDialog(self.app, amount=amount, make_tx=make_tx, on_pay=on_pay)
         d.open()