Merge branch 'master' into jgrpp

# Conflicts:
#	regression/regression/result.txt
#	src/aircraft_cmd.cpp
#	src/airport_gui.cpp
#	src/articulated_vehicles.cpp
#	src/console_cmds.cpp
#	src/date_gui.cpp
#	src/engine.cpp
#	src/genworld_gui.cpp
#	src/gfx_layout_fallback.cpp
#	src/group_gui.cpp
#	src/hotkeys.cpp
#	src/network/core/tcp_connect.cpp
#	src/network/core/tcp_listen.h
#	src/newgrf.cpp
#	src/newgrf.h
#	src/newgrf_engine.cpp
#	src/newgrf_gui.cpp
#	src/newgrf_station.cpp
#	src/openttd.cpp
#	src/order_gui.cpp
#	src/os/macosx/osx_main.cpp
#	src/pathfinder/yapf/yapf_node_rail.hpp
#	src/rail_gui.cpp
#	src/saveload/afterload.cpp
#	src/saveload/cargopacket_sl.cpp
#	src/saveload/linkgraph_sl.cpp
#	src/saveload/station_sl.cpp
#	src/script/api/script_industrytype.cpp
#	src/settings.cpp
#	src/settings_gui.cpp
#	src/settings_table.cpp
#	src/settingsgen/settingsgen.cpp
#	src/station.cpp
#	src/station_cmd.cpp
#	src/strings.cpp
#	src/timer/timer_game_calendar.cpp
#	src/timer/timer_game_calendar.h
#	src/timer/timer_manager.h
#	src/timer/timer_window.cpp
#	src/timetable_cmd.cpp
#	src/toolbar_gui.cpp
#	src/town_cmd.cpp
#	src/town_gui.cpp
#	src/train_gui.cpp
#	src/vehicle_cmd.h
#	src/vehicle_gui.cpp
#	src/viewport.cpp
#	src/widgets/dropdown.cpp
#	src/window_func.h
#	src/window_gui.h

src/town_gui.cpp

@@ -534,7 +534,7 @@ public:
 		nvp->InitializeViewport(this, this->town->xy, ScaleZoomGUI(ZOOM_LVL_TOWN));
 	}
 
-	void Close() override
+	void Close([[maybe_unused]] int data = 0) override
 	{
 		SetViewportCatchmentTown(Town::Get(this->window_number), false);
 		this->Window::Close();
@@ -673,14 +673,6 @@ public:
 				break;
 
 			case WID_TV_EXPAND: { // expand town - only available on Scenario editor
-				/* Warn the user if towns are not allowed to build roads, but do this only once per OpenTTD run. */
-				static bool _warn_town_no_roads = false;
-
-				if (!Town::Get(this->window_number)->GetAllowBuildRoads() && !_warn_town_no_roads) {
-					ShowErrorMessage(STR_ERROR_TOWN_EXPAND_WARN_NO_ROADS, INVALID_STRING_ID, WL_WARNING);
-					_warn_town_no_roads = true;
-				}
-
 				DoCommandP(0, this->window_number, 0, CMD_EXPAND_TOWN | CMD_MSG(STR_ERROR_CAN_T_EXPAND_TOWN));
 				break;
 			}
@@ -1013,7 +1005,7 @@ public:
 			case WID_TD_LIST: {
 				int n = 0;
 				Rect tr = r.Shrink(WidgetDimensions::scaled.framerect);
-				if (this->towns.size() == 0) { // No towns available.
+				if (this->towns.empty()) { // No towns available.
 					DrawString(tr, STR_TOWN_DIRECTORY_NONE);
 					break;
 				}