qt confirm_tx_dialog: show frozen balance if "not enough funds"

electrum/gui/qt/confirm_tx_dialog.py

@@ -535,8 +535,9 @@ class TxEditor(WindowModalDialog):
                 self.error += ' ' + _('Change your settings to allow spending unconfirmed coins.')
             elif self.can_pay_assuming_zero_fees(confirmed_only=confirmed_only):
                 self.error += ' ' + _('You need to set a lower fee.')
-            else:
-                self.error += ''
+            elif frozen_bal := self.wallet.get_frozen_balance_str():
+                # FIXME only show if unfreezing would fix "not enough funds"
+                self.error += ' ' + _("Some coins are frozen: {} (can be unfrozen in the Addresses or in the Coins tab)").format(frozen_bal)
         if not self.tx:
             if self.not_enough_funds:
                 self.io_widget.update(None)
@@ -616,6 +617,9 @@ class TxEditor(WindowModalDialog):
         self.preview_button.setEnabled(enabled)
         self.ok_button.setEnabled(enabled)
 
+    def can_pay_assuming_zero_fees(self, confirmed_only: bool) -> bool:
+        raise NotImplementedError
+
 
 class ConfirmTxDialog(TxEditor):
     help_text = ''  #_('Set the mining fee of your transaction')
@@ -681,7 +685,7 @@ class ConfirmTxDialog(TxEditor):
             raise
         self.tx.set_rbf(True)
 
-    def can_pay_assuming_zero_fees(self, confirmed_only) -> bool:
+    def can_pay_assuming_zero_fees(self, confirmed_only: bool) -> bool:
         # called in send_tab.py
         try:
             tx = self.make_tx(FixedFeePolicy(0), confirmed_only=confirmed_only, base_tx=None)

electrum/gui/qt/main_window.py

@@ -1418,7 +1418,7 @@ class ElectrumWindow(QMainWindow, MessageBoxMixin, Logger, QtEventListener):
 
     def confirm_tx_dialog(self, make_tx, output_value, allow_preview=True, batching_candidates=None):
         d = ConfirmTxDialog(window=self, make_tx=make_tx, output_value=output_value, allow_preview=allow_preview, batching_candidates=batching_candidates)
-        if d.not_enough_funds:
+        if d.not_enough_funds:  # FIXME this check looks broken?
             # note: use confirmed_only=False here, regardless of config setting,
             #       as the user needs to get to ConfirmTxDialog to change the config setting
             if not d.can_pay_assuming_zero_fees(confirmed_only=False):