config: add option to display amounts with msat precision

electrum/gui/qt/settings_dialog.py

@@ -98,8 +98,7 @@ class SettingsDialog(WindowModalDialog):
             if self.config.num_zeros != value:
                 self.config.num_zeros = value
                 self.config.set_key('num_zeros', value, True)
-                self.window.history_list.update()
-                self.window.address_list.update()
+                self.window.need_update.set()
         nz.valueChanged.connect(on_nz)
         gui_widgets.append((nz_label, nz))
 
@@ -191,6 +190,17 @@ class SettingsDialog(WindowModalDialog):
         self.alias_e.editingFinished.connect(self.on_alias_edit)
         oa_widgets.append((alias_label, self.alias_e))
 
+        msat_cb = QCheckBox(_("Show amounts with msat precision"))
+        msat_cb.setChecked(bool(self.config.get('amt_precision_post_satoshi', False)))
+        def on_msat_checked(b: bool):
+            prec = 3 if b else 0
+            if self.config.amt_precision_post_satoshi != prec:
+                self.config.amt_precision_post_satoshi = prec
+                self.config.set_key('amt_precision_post_satoshi', prec)
+                self.window.need_update.set()
+        msat_cb.stateChanged.connect(on_msat_checked)
+        lightning_widgets.append((msat_cb, None))
+
         # units
         units = base_units_list
         msg = (_('Base unit of your wallet.')

electrum/simple_config.py

@@ -110,6 +110,7 @@ class SimpleConfig(Logger):
         except UnknownBaseUnit:
             self.decimal_point = DECIMAL_POINT_DEFAULT
         self.num_zeros = int(self.get('num_zeros', 0))
+        self.amt_precision_post_satoshi = int(self.get('amt_precision_post_satoshi', 0))
 
     def electrum_path(self):
         # Read electrum_path from command line
@@ -665,6 +666,7 @@ class SimpleConfig(Logger):
             decimal_point=self.decimal_point,
             is_diff=is_diff,
             whitespaces=whitespaces,
+            precision=self.amt_precision_post_satoshi,
         )
 
     def format_amount_and_units(self, amount):