qt: don't update tabs in ElectrumWindow.__init__ directly

electrum/gui/qt/main_window.py

@@ -354,10 +354,9 @@ class ElectrumWindow(QMainWindow, MessageBoxMixin, PrintError):
         wallet.thread = TaskThread(self, self.on_error)
         self.wallet = wallet
         self.update_recently_visited(wallet.storage.path)
-        # address used to create a dummy transaction and estimate transaction fee
-        self.history_list.update()
-        self.address_list.update()
-        self.utxo_list.update()
+        # update(==init) all tabs; expensive for large wallets..
+        # so delay it somewhat, hence __init__ can finish and the window can appear sooner
+        QTimer.singleShot(50, self.update_tabs)
         self.need_update.set()
         # Once GUI has been initialized check if we want to announce something since the callback has been called before the GUI was initialized
         # update menus