diff --git a/.github/windowdesc-ini-key.py b/.github/windowdesc-ini-key.py
index 16fa3053d8..36b20f9948 100644
--- a/.github/windowdesc-ini-key.py
+++ b/.github/windowdesc-ini-key.py
@@ -22,7 +22,7 @@ def scan_source_files(path, ini_keys=None):
         with open(new_path) as fp:
             output = fp.read()
 
-        for (name, ini_key, widgets) in re.findall(r"^static WindowDesc ([a-zA-Z0-9_]*).*?, (?:\"(.*?)\")?.*?,(?:\s+(.*?),){6}", output, re.S|re.M):
+        for (name, ini_key, widgets) in re.findall(r"^static WindowDesc ([a-zA-Z0-9_]*).*?, (?:\"(.*?)\")?.*?,(?:\s+.*?,){6}\s+[^\s]+\((.*?)\)", output, re.S|re.M):
             if ini_key:
                 if ini_key in ini_keys:
                     errors.append(f"{new_path}: {name} ini_key is a duplicate")
diff --git a/src/ai/ai_gui.cpp b/src/ai/ai_gui.cpp
index a74586246d..b3125e8c2e 100644
--- a/src/ai/ai_gui.cpp
+++ b/src/ai/ai_gui.cpp
@@ -77,7 +77,7 @@ static WindowDesc _ai_config_desc(
 	WDP_CENTER, "settings_script_config", 0, 0,
 	WC_GAME_OPTIONS, WC_NONE,
 	0,
-	_nested_ai_config_widgets, lengthof(_nested_ai_config_widgets)
+	std::begin(_nested_ai_config_widgets), std::end(_nested_ai_config_widgets)
 );
 
 /**
diff --git a/src/airport_gui.cpp b/src/airport_gui.cpp
index fe0e6f7f39..ac9b0448e3 100644
--- a/src/airport_gui.cpp
+++ b/src/airport_gui.cpp
@@ -213,7 +213,7 @@ static WindowDesc _air_toolbar_desc(
 	WDP_ALIGN_TOOLBAR, "toolbar_air", 0, 0,
 	WC_BUILD_TOOLBAR, WC_NONE,
 	WDF_CONSTRUCTION,
-	_nested_air_toolbar_widgets, lengthof(_nested_air_toolbar_widgets),
+	std::begin(_nested_air_toolbar_widgets), std::end(_nested_air_toolbar_widgets),
 	&BuildAirToolbarWindow::hotkeys
 );
 
@@ -622,7 +622,7 @@ static WindowDesc _build_airport_desc(
 	WDP_AUTO, nullptr, 0, 0,
 	WC_BUILD_STATION, WC_BUILD_TOOLBAR,
 	WDF_CONSTRUCTION,
-	_nested_build_airport_widgets, lengthof(_nested_build_airport_widgets)
+	std::begin(_nested_build_airport_widgets), std::end(_nested_build_airport_widgets)
 );
 
 static void ShowBuildAirportPicker(Window *parent)
diff --git a/src/autoreplace_gui.cpp b/src/autoreplace_gui.cpp
index 1be79d5aee..8b342ca712 100644
--- a/src/autoreplace_gui.cpp
+++ b/src/autoreplace_gui.cpp
@@ -808,7 +808,7 @@ static WindowDesc _replace_rail_vehicle_desc(
 	WDP_AUTO, "replace_vehicle_train", 500, 140,
 	WC_REPLACE_VEHICLE, WC_NONE,
 	WDF_CONSTRUCTION,
-	_nested_replace_rail_vehicle_widgets, lengthof(_nested_replace_rail_vehicle_widgets)
+	std::begin(_nested_replace_rail_vehicle_widgets), std::end(_nested_replace_rail_vehicle_widgets)
 );
 
 static const NWidgetPart _nested_replace_road_vehicle_widgets[] = {
@@ -866,7 +866,7 @@ static WindowDesc _replace_road_vehicle_desc(
 	WDP_AUTO, "replace_vehicle_road", 500, 140,
 	WC_REPLACE_VEHICLE, WC_NONE,
 	WDF_CONSTRUCTION,
-	_nested_replace_road_vehicle_widgets, lengthof(_nested_replace_road_vehicle_widgets)
+	std::begin(_nested_replace_road_vehicle_widgets), std::end(_nested_replace_road_vehicle_widgets)
 );
 
 static const NWidgetPart _nested_replace_vehicle_widgets[] = {
@@ -920,7 +920,7 @@ static WindowDesc _replace_vehicle_desc(
 	WDP_AUTO, "replace_vehicle", 456, 118,
 	WC_REPLACE_VEHICLE, WC_NONE,
 	WDF_CONSTRUCTION,
-	_nested_replace_vehicle_widgets, lengthof(_nested_replace_vehicle_widgets)
+	std::begin(_nested_replace_vehicle_widgets), std::end(_nested_replace_vehicle_widgets)
 );
 
 /**
diff --git a/src/bootstrap_gui.cpp b/src/bootstrap_gui.cpp
index 063e908a32..386883c1e2 100644
--- a/src/bootstrap_gui.cpp
+++ b/src/bootstrap_gui.cpp
@@ -43,7 +43,7 @@ static WindowDesc _background_desc(
 	WDP_MANUAL, nullptr, 0, 0,
 	WC_BOOTSTRAP, WC_NONE,
 	WDF_NO_CLOSE,
-	_background_widgets, lengthof(_background_widgets)
+	std::begin(_background_widgets), std::end(_background_widgets)
 );
 
 /** The background for the game. */
@@ -81,7 +81,7 @@ static WindowDesc _bootstrap_errmsg_desc(
 	WDP_CENTER, nullptr, 0, 0,
 	WC_BOOTSTRAP, WC_NONE,
 	WDF_MODAL | WDF_NO_CLOSE,
-	_nested_bootstrap_errmsg_widgets, lengthof(_nested_bootstrap_errmsg_widgets)
+	std::begin(_nested_bootstrap_errmsg_widgets), std::end(_nested_bootstrap_errmsg_widgets)
 );
 
 /** The window for a failed bootstrap. */
@@ -138,7 +138,7 @@ static WindowDesc _bootstrap_download_status_window_desc(
 	WDP_CENTER, nullptr, 0, 0,
 	WC_NETWORK_STATUS_WINDOW, WC_NONE,
 	WDF_MODAL | WDF_NO_CLOSE,
-	_nested_bootstrap_download_status_window_widgets, lengthof(_nested_bootstrap_download_status_window_widgets)
+	std::begin(_nested_bootstrap_download_status_window_widgets), std::end(_nested_bootstrap_download_status_window_widgets)
 );
 
 
@@ -192,7 +192,7 @@ static WindowDesc _bootstrap_query_desc(
 	WDP_CENTER, nullptr, 0, 0,
 	WC_CONFIRM_POPUP_QUERY, WC_NONE,
 	WDF_NO_CLOSE,
-	_bootstrap_query_widgets, lengthof(_bootstrap_query_widgets)
+	std::begin(_bootstrap_query_widgets), std::end(_bootstrap_query_widgets)
 );
 
 /** The window for the query. It can't use the generic query window as that uses sprites that don't exist yet. */
diff --git a/src/bridge_gui.cpp b/src/bridge_gui.cpp
index a463f51537..367e634411 100644
--- a/src/bridge_gui.cpp
+++ b/src/bridge_gui.cpp
@@ -346,7 +346,7 @@ static WindowDesc _build_bridge_desc(
 	WDP_AUTO, "build_bridge", 200, 114,
 	WC_BUILD_BRIDGE, WC_BUILD_TOOLBAR,
 	WDF_CONSTRUCTION,
-	_nested_build_bridge_widgets, lengthof(_nested_build_bridge_widgets)
+	std::begin(_nested_build_bridge_widgets), std::end(_nested_build_bridge_widgets)
 );
 
 /**
diff --git a/src/build_vehicle_gui.cpp b/src/build_vehicle_gui.cpp
index 86563ad8d9..7c5a259933 100644
--- a/src/build_vehicle_gui.cpp
+++ b/src/build_vehicle_gui.cpp
@@ -1885,7 +1885,7 @@ static WindowDesc _build_vehicle_desc(
 	WDP_AUTO, "build_vehicle", 240, 268,
 	WC_BUILD_VEHICLE, WC_NONE,
 	WDF_CONSTRUCTION,
-	_nested_build_vehicle_widgets, lengthof(_nested_build_vehicle_widgets),
+	std::begin(_nested_build_vehicle_widgets), std::end(_nested_build_vehicle_widgets),
 	&BuildVehicleWindow::hotkeys
 );
 
diff --git a/src/cheat_gui.cpp b/src/cheat_gui.cpp
index 5e5c97c98b..e058a27cf7 100644
--- a/src/cheat_gui.cpp
+++ b/src/cheat_gui.cpp
@@ -432,7 +432,7 @@ static WindowDesc _cheats_desc(
 	WDP_AUTO, "cheats", 0, 0,
 	WC_CHEATS, WC_NONE,
 	0,
-	_nested_cheat_widgets, lengthof(_nested_cheat_widgets)
+	std::begin(_nested_cheat_widgets), std::end(_nested_cheat_widgets)
 );
 
 /** Open cheat window. */
diff --git a/src/company_gui.cpp b/src/company_gui.cpp
index 409c57a276..45ca97f8e3 100644
--- a/src/company_gui.cpp
+++ b/src/company_gui.cpp
@@ -542,7 +542,7 @@ static WindowDesc _company_finances_desc(
 	WDP_AUTO, "company_finances", 0, 0,
 	WC_FINANCES, WC_NONE,
 	0,
-	_nested_company_finances_widgets, lengthof(_nested_company_finances_widgets)
+	std::begin(_nested_company_finances_widgets), std::end(_nested_company_finances_widgets)
 );
 
 /**
@@ -1160,7 +1160,7 @@ static WindowDesc _select_company_livery_desc(
 	WDP_AUTO, nullptr, 0, 0,
 	WC_COMPANY_COLOUR, WC_NONE,
 	0,
-	_nested_select_company_livery_widgets, lengthof(_nested_select_company_livery_widgets)
+	std::begin(_nested_select_company_livery_widgets), std::end(_nested_select_company_livery_widgets)
 );
 
 void ShowCompanyLiveryWindow(CompanyID company, GroupID group)
@@ -1777,7 +1777,7 @@ static WindowDesc _select_company_manager_face_desc(
 	WDP_AUTO, nullptr, 0, 0,
 	WC_COMPANY_MANAGER_FACE, WC_NONE,
 	WDF_CONSTRUCTION,
-	_nested_select_company_manager_face_widgets, lengthof(_nested_select_company_manager_face_widgets)
+	std::begin(_nested_select_company_manager_face_widgets), std::end(_nested_select_company_manager_face_widgets)
 );
 
 /**
@@ -2149,7 +2149,7 @@ static WindowDesc _company_infrastructure_desc(
 	WDP_AUTO, "company_infrastructure", 0, 0,
 	WC_COMPANY_INFRASTRUCTURE, WC_NONE,
 	0,
-	_nested_company_infrastructure_widgets, lengthof(_nested_company_infrastructure_widgets)
+	std::begin(_nested_company_infrastructure_widgets), std::end(_nested_company_infrastructure_widgets)
 );
 
 /**
@@ -2686,7 +2686,7 @@ static WindowDesc _company_desc(
 	WDP_AUTO, "company", 0, 0,
 	WC_COMPANY, WC_NONE,
 	0,
-	_nested_company_widgets, lengthof(_nested_company_widgets)
+	std::begin(_nested_company_widgets), std::end(_nested_company_widgets)
 );
 
 /**
@@ -2820,7 +2820,7 @@ static WindowDesc _buy_company_desc(
 	WDP_AUTO, nullptr, 0, 0,
 	WC_BUY_COMPANY, WC_NONE,
 	WDF_CONSTRUCTION,
-	_nested_buy_company_widgets, lengthof(_nested_buy_company_widgets)
+	std::begin(_nested_buy_company_widgets), std::end(_nested_buy_company_widgets)
 );
 
 /**
diff --git a/src/console_gui.cpp b/src/console_gui.cpp
index ce2c0df758..3fc5e68288 100644
--- a/src/console_gui.cpp
+++ b/src/console_gui.cpp
@@ -106,7 +106,7 @@ static WindowDesc _console_window_desc(
 	WDP_MANUAL, nullptr, 0, 0,
 	WC_CONSOLE, WC_NONE,
 	0,
-	_nested_console_window_widgets, lengthof(_nested_console_window_widgets)
+	std::begin(_nested_console_window_widgets), std::end(_nested_console_window_widgets)
 );
 
 struct IConsoleWindow : Window
diff --git a/src/date_gui.cpp b/src/date_gui.cpp
index febf505836..cc012f545b 100644
--- a/src/date_gui.cpp
+++ b/src/date_gui.cpp
@@ -200,7 +200,7 @@ static WindowDesc _set_date_desc(
 	WDP_CENTER, nullptr, 0, 0,
 	WC_SET_DATE, WC_NONE,
 	0,
-	_nested_set_date_widgets, lengthof(_nested_set_date_widgets)
+	std::begin(_nested_set_date_widgets), std::end(_nested_set_date_widgets)
 );
 
 /**
diff --git a/src/depot_gui.cpp b/src/depot_gui.cpp
index b7fb593a45..4a7ada72fb 100644
--- a/src/depot_gui.cpp
+++ b/src/depot_gui.cpp
@@ -89,28 +89,28 @@ static WindowDesc _train_depot_desc(
 	WDP_AUTO, "depot_train", 362, 123,
 	WC_VEHICLE_DEPOT, WC_NONE,
 	0,
-	_nested_train_depot_widgets, lengthof(_nested_train_depot_widgets)
+	std::begin(_nested_train_depot_widgets), std::end(_nested_train_depot_widgets)
 );
 
 static WindowDesc _road_depot_desc(
 	WDP_AUTO, "depot_roadveh", 316, 97,
 	WC_VEHICLE_DEPOT, WC_NONE,
 	0,
-	_nested_train_depot_widgets, lengthof(_nested_train_depot_widgets)
+	std::begin(_nested_train_depot_widgets), std::end(_nested_train_depot_widgets)
 );
 
 static WindowDesc _ship_depot_desc(
 	WDP_AUTO, "depot_ship", 306, 99,
 	WC_VEHICLE_DEPOT, WC_NONE,
 	0,
-	_nested_train_depot_widgets, lengthof(_nested_train_depot_widgets)
+	std::begin(_nested_train_depot_widgets), std::end(_nested_train_depot_widgets)
 );
 
 static WindowDesc _aircraft_depot_desc(
 	WDP_AUTO, "depot_aircraft", 332, 99,
 	WC_VEHICLE_DEPOT, WC_NONE,
 	0,
-	_nested_train_depot_widgets, lengthof(_nested_train_depot_widgets)
+	std::begin(_nested_train_depot_widgets), std::end(_nested_train_depot_widgets)
 );
 
 extern void DepotSortList(VehicleList *list);
diff --git a/src/dock_gui.cpp b/src/dock_gui.cpp
index 6bdaa75d38..f2a4d60305 100644
--- a/src/dock_gui.cpp
+++ b/src/dock_gui.cpp
@@ -349,7 +349,7 @@ static WindowDesc _build_docks_toolbar_desc(
 	WDP_ALIGN_TOOLBAR, "toolbar_water", 0, 0,
 	WC_BUILD_TOOLBAR, WC_NONE,
 	WDF_CONSTRUCTION,
-	_nested_build_docks_toolbar_widgets, lengthof(_nested_build_docks_toolbar_widgets),
+	std::begin(_nested_build_docks_toolbar_widgets), std::end(_nested_build_docks_toolbar_widgets),
 	&BuildDocksToolbarWindow::hotkeys
 );
 
@@ -393,7 +393,7 @@ static WindowDesc _build_docks_scen_toolbar_desc(
 	WDP_AUTO, "toolbar_water_scen", 0, 0,
 	WC_SCEN_BUILD_TOOLBAR, WC_NONE,
 	WDF_CONSTRUCTION,
-	_nested_build_docks_scen_toolbar_widgets, lengthof(_nested_build_docks_scen_toolbar_widgets)
+	std::begin(_nested_build_docks_scen_toolbar_widgets), std::end(_nested_build_docks_scen_toolbar_widgets)
 );
 
 /**
@@ -499,7 +499,7 @@ static WindowDesc _build_dock_station_desc(
 	WDP_AUTO, nullptr, 0, 0,
 	WC_BUILD_STATION, WC_BUILD_TOOLBAR,
 	WDF_CONSTRUCTION,
-	_nested_build_dock_station_widgets, lengthof(_nested_build_dock_station_widgets)
+	std::begin(_nested_build_dock_station_widgets), std::end(_nested_build_dock_station_widgets)
 );
 
 static void ShowBuildDockStationPicker(Window *parent)
@@ -597,7 +597,7 @@ static WindowDesc _build_docks_depot_desc(
 	WDP_AUTO, nullptr, 0, 0,
 	WC_BUILD_DEPOT, WC_BUILD_TOOLBAR,
 	WDF_CONSTRUCTION,
-	_nested_build_docks_depot_widgets, lengthof(_nested_build_docks_depot_widgets)
+	std::begin(_nested_build_docks_depot_widgets), std::end(_nested_build_docks_depot_widgets)
 );
 
 
diff --git a/src/engine_gui.cpp b/src/engine_gui.cpp
index d909196b8c..ea580ffe31 100644
--- a/src/engine_gui.cpp
+++ b/src/engine_gui.cpp
@@ -147,7 +147,7 @@ static WindowDesc _engine_preview_desc(
 	WDP_CENTER, nullptr, 0, 0,
 	WC_ENGINE_PREVIEW, WC_NONE,
 	WDF_CONSTRUCTION,
-	_nested_engine_preview_widgets, lengthof(_nested_engine_preview_widgets)
+	std::begin(_nested_engine_preview_widgets), std::end(_nested_engine_preview_widgets)
 );
 
 
diff --git a/src/error_gui.cpp b/src/error_gui.cpp
index 7702b43578..2aacc1eed8 100644
--- a/src/error_gui.cpp
+++ b/src/error_gui.cpp
@@ -46,7 +46,7 @@ static WindowDesc _errmsg_desc(
 	WDP_MANUAL, nullptr, 0, 0,
 	WC_ERRMSG, WC_NONE,
 	0,
-	_nested_errmsg_widgets, lengthof(_nested_errmsg_widgets)
+	std::begin(_nested_errmsg_widgets), std::end(_nested_errmsg_widgets)
 );
 
 static const NWidgetPart _nested_errmsg_face_widgets[] = {
@@ -66,7 +66,7 @@ static WindowDesc _errmsg_face_desc(
 	WDP_MANUAL, nullptr, 0, 0,
 	WC_ERRMSG, WC_NONE,
 	0,
-	_nested_errmsg_face_widgets, lengthof(_nested_errmsg_face_widgets)
+	std::begin(_nested_errmsg_face_widgets), std::end(_nested_errmsg_face_widgets)
 );
 
 /**
diff --git a/src/fios_gui.cpp b/src/fios_gui.cpp
index 67883c9a9c..8eb5c7255a 100644
--- a/src/fios_gui.cpp
+++ b/src/fios_gui.cpp
@@ -887,7 +887,7 @@ static WindowDesc _load_dialog_desc(
 	WDP_CENTER, "load_game", 500, 294,
 	WC_SAVELOAD, WC_NONE,
 	0,
-	_nested_load_dialog_widgets, lengthof(_nested_load_dialog_widgets)
+	std::begin(_nested_load_dialog_widgets), std::end(_nested_load_dialog_widgets)
 );
 
 /** Load heightmap */
@@ -895,7 +895,7 @@ static WindowDesc _load_heightmap_dialog_desc(
 	WDP_CENTER, "load_heightmap", 257, 320,
 	WC_SAVELOAD, WC_NONE,
 	0,
-	_nested_load_heightmap_dialog_widgets, lengthof(_nested_load_heightmap_dialog_widgets)
+	std::begin(_nested_load_heightmap_dialog_widgets), std::end(_nested_load_heightmap_dialog_widgets)
 );
 
 /** Save game/scenario */
@@ -903,7 +903,7 @@ static WindowDesc _save_dialog_desc(
 	WDP_CENTER, "save_game", 500, 294,
 	WC_SAVELOAD, WC_NONE,
 	0,
-	_nested_save_dialog_widgets, lengthof(_nested_save_dialog_widgets)
+	std::begin(_nested_save_dialog_widgets), std::end(_nested_save_dialog_widgets)
 );
 
 /**
diff --git a/src/framerate_gui.cpp b/src/framerate_gui.cpp
index 7b416e750e..453d9f142f 100644
--- a/src/framerate_gui.cpp
+++ b/src/framerate_gui.cpp
@@ -730,7 +730,7 @@ static WindowDesc _framerate_display_desc(
 	WDP_AUTO, "framerate_display", 0, 0,
 	WC_FRAMERATE_DISPLAY, WC_NONE,
 	0,
-	_framerate_window_widgets, lengthof(_framerate_window_widgets)
+	std::begin(_framerate_window_widgets), std::end(_framerate_window_widgets)
 );
 
 
@@ -1015,7 +1015,7 @@ static WindowDesc _frametime_graph_window_desc(
 	WDP_AUTO, "frametime_graph", 140, 90,
 	WC_FRAMETIME_GRAPH, WC_NONE,
 	0,
-	_frametime_graph_window_widgets, lengthof(_frametime_graph_window_widgets)
+	std::begin(_frametime_graph_window_widgets), std::end(_frametime_graph_window_widgets)
 );
 
 
diff --git a/src/game/game_gui.cpp b/src/game/game_gui.cpp
index f926409086..6a1c89596d 100644
--- a/src/game/game_gui.cpp
+++ b/src/game/game_gui.cpp
@@ -72,7 +72,7 @@ static WindowDesc _gs_config_desc(
 	WDP_CENTER, "settings_gs_config", 500, 350,
 	WC_GAME_OPTIONS, WC_NONE,
 	0,
-	_nested_gs_config_widgets, lengthof(_nested_gs_config_widgets)
+	std::begin(_nested_gs_config_widgets), std::end(_nested_gs_config_widgets)
 );
 
 /**
diff --git a/src/genworld_gui.cpp b/src/genworld_gui.cpp
index 669e597f78..294b60c55e 100644
--- a/src/genworld_gui.cpp
+++ b/src/genworld_gui.cpp
@@ -1025,14 +1025,14 @@ static WindowDesc _generate_landscape_desc(
 	WDP_CENTER, nullptr, 0, 0,
 	WC_GENERATE_LANDSCAPE, WC_NONE,
 	0,
-	_nested_generate_landscape_widgets, lengthof(_nested_generate_landscape_widgets)
+	std::begin(_nested_generate_landscape_widgets), std::end(_nested_generate_landscape_widgets)
 );
 
 static WindowDesc _heightmap_load_desc(
 	WDP_CENTER, nullptr, 0, 0,
 	WC_GENERATE_LANDSCAPE, WC_NONE,
 	0,
-	_nested_heightmap_load_widgets, lengthof(_nested_heightmap_load_widgets)
+	std::begin(_nested_heightmap_load_widgets), std::end(_nested_heightmap_load_widgets)
 );
 
 static void _ShowGenerateLandscape(GenerateLandscapeWindowMode mode)
@@ -1328,7 +1328,7 @@ static WindowDesc _create_scenario_desc(
 	WDP_CENTER, nullptr, 0, 0,
 	WC_GENERATE_LANDSCAPE, WC_NONE,
 	0,
-	_nested_create_scenario_widgets, lengthof(_nested_create_scenario_widgets)
+	std::begin(_nested_create_scenario_widgets), std::end(_nested_create_scenario_widgets)
 );
 
 /** Show the window to create a scenario. */
@@ -1354,7 +1354,7 @@ static WindowDesc _generate_progress_desc(
 	WDP_CENTER, nullptr, 0, 0,
 	WC_MODAL_PROGRESS, WC_NONE,
 	0,
-	_nested_generate_progress_widgets, lengthof(_nested_generate_progress_widgets)
+	std::begin(_nested_generate_progress_widgets), std::end(_nested_generate_progress_widgets)
 );
 
 struct GenWorldStatus {
diff --git a/src/goal_gui.cpp b/src/goal_gui.cpp
index bc640b0209..9ff4a32738 100644
--- a/src/goal_gui.cpp
+++ b/src/goal_gui.cpp
@@ -306,7 +306,7 @@ static WindowDesc _goals_list_desc(
 	WDP_AUTO, "list_goals", 500, 127,
 	WC_GOALS_LIST, WC_NONE,
 	0,
-	_nested_goals_list_widgets, lengthof(_nested_goals_list_widgets)
+	std::begin(_nested_goals_list_widgets), std::end(_nested_goals_list_widgets)
 );
 
 /**
@@ -521,25 +521,25 @@ static WindowDesc _goal_question_list_desc[] = {
 		WDP_CENTER, nullptr, 0, 0,
 		WC_GOAL_QUESTION, WC_NONE,
 		WDF_CONSTRUCTION,
-		_nested_goal_question_widgets_question, lengthof(_nested_goal_question_widgets_question),
+		std::begin(_nested_goal_question_widgets_question), std::end(_nested_goal_question_widgets_question),
 	},
 	{
 		WDP_CENTER, nullptr, 0, 0,
 		WC_GOAL_QUESTION, WC_NONE,
 		WDF_CONSTRUCTION,
-		_nested_goal_question_widgets_info, lengthof(_nested_goal_question_widgets_info),
+		std::begin(_nested_goal_question_widgets_info), std::end(_nested_goal_question_widgets_info),
 	},
 	{
 		WDP_CENTER, nullptr, 0, 0,
 		WC_GOAL_QUESTION, WC_NONE,
 		WDF_CONSTRUCTION,
-		_nested_goal_question_widgets_warning, lengthof(_nested_goal_question_widgets_warning),
+		std::begin(_nested_goal_question_widgets_warning), std::end(_nested_goal_question_widgets_warning),
 	},
 	{
 		WDP_CENTER, nullptr, 0, 0,
 		WC_GOAL_QUESTION, WC_NONE,
 		WDF_CONSTRUCTION,
-		_nested_goal_question_widgets_error, lengthof(_nested_goal_question_widgets_error),
+		std::begin(_nested_goal_question_widgets_error), std::end(_nested_goal_question_widgets_error),
 	},
 };
 
diff --git a/src/graph_gui.cpp b/src/graph_gui.cpp
index dba31fe4fe..91179e8286 100644
--- a/src/graph_gui.cpp
+++ b/src/graph_gui.cpp
@@ -145,7 +145,7 @@ static WindowDesc _graph_legend_desc(
 	WDP_AUTO, "graph_legend", 0, 0,
 	WC_GRAPH_LEGEND, WC_NONE,
 	0,
-	_nested_graph_legend_widgets, lengthof(_nested_graph_legend_widgets)
+	std::begin(_nested_graph_legend_widgets), std::end(_nested_graph_legend_widgets)
 );
 
 static void ShowGraphLegend()
@@ -658,7 +658,7 @@ static WindowDesc _operating_profit_desc(
 	WDP_AUTO, "graph_operating_profit", 0, 0,
 	WC_OPERATING_PROFIT, WC_NONE,
 	0,
-	_nested_operating_profit_widgets, lengthof(_nested_operating_profit_widgets)
+	std::begin(_nested_operating_profit_widgets), std::end(_nested_operating_profit_widgets)
 );
 
 
@@ -709,7 +709,7 @@ static WindowDesc _income_graph_desc(
 	WDP_AUTO, "graph_income", 0, 0,
 	WC_INCOME_GRAPH, WC_NONE,
 	0,
-	_nested_income_graph_widgets, lengthof(_nested_income_graph_widgets)
+	std::begin(_nested_income_graph_widgets), std::end(_nested_income_graph_widgets)
 );
 
 void ShowIncomeGraph()
@@ -758,7 +758,7 @@ static WindowDesc _delivered_cargo_graph_desc(
 	WDP_AUTO, "graph_delivered_cargo", 0, 0,
 	WC_DELIVERED_CARGO, WC_NONE,
 	0,
-	_nested_delivered_cargo_graph_widgets, lengthof(_nested_delivered_cargo_graph_widgets)
+	std::begin(_nested_delivered_cargo_graph_widgets), std::end(_nested_delivered_cargo_graph_widgets)
 );
 
 void ShowDeliveredCargoGraph()
@@ -814,7 +814,7 @@ static WindowDesc _performance_history_desc(
 	WDP_AUTO, "graph_performance", 0, 0,
 	WC_PERFORMANCE_HISTORY, WC_NONE,
 	0,
-	_nested_performance_history_widgets, lengthof(_nested_performance_history_widgets)
+	std::begin(_nested_performance_history_widgets), std::end(_nested_performance_history_widgets)
 );
 
 void ShowPerformanceHistoryGraph()
@@ -863,7 +863,7 @@ static WindowDesc _company_value_graph_desc(
 	WDP_AUTO, "graph_company_value", 0, 0,
 	WC_COMPANY_VALUE, WC_NONE,
 	0,
-	_nested_company_value_graph_widgets, lengthof(_nested_company_value_graph_widgets)
+	std::begin(_nested_company_value_graph_widgets), std::end(_nested_company_value_graph_widgets)
 );
 
 void ShowCompanyValueGraph()
@@ -1097,7 +1097,7 @@ static WindowDesc _cargo_payment_rates_desc(
 	WDP_AUTO, "graph_cargo_payment_rates", 0, 0,
 	WC_PAYMENT_RATES, WC_NONE,
 	0,
-	_nested_cargo_payment_rates_widgets, lengthof(_nested_cargo_payment_rates_widgets)
+	std::begin(_nested_cargo_payment_rates_widgets), std::end(_nested_cargo_payment_rates_widgets)
 );
 
 
@@ -1393,7 +1393,7 @@ static WindowDesc _performance_rating_detail_desc(
 	WDP_AUTO, "league_details", 0, 0,
 	WC_PERFORMANCE_DETAIL, WC_NONE,
 	0,
-	_nested_performance_rating_detail_widgets, lengthof(_nested_performance_rating_detail_widgets)
+	std::begin(_nested_performance_rating_detail_widgets), std::end(_nested_performance_rating_detail_widgets)
 );
 
 void ShowPerformanceRatingDetail()
diff --git a/src/group_gui.cpp b/src/group_gui.cpp
index cb6959d379..721125d62a 100644
--- a/src/group_gui.cpp
+++ b/src/group_gui.cpp
@@ -1108,14 +1108,14 @@ static WindowDesc _other_group_desc(
 	WDP_AUTO, "list_groups", 460, 246,
 	WC_INVALID, WC_NONE,
 	0,
-	_nested_group_widgets, lengthof(_nested_group_widgets)
+	std::begin(_nested_group_widgets), std::end(_nested_group_widgets)
 );
 
 static WindowDesc _train_group_desc(
 	WDP_AUTO, "list_groups_train", 525, 246,
 	WC_TRAINS_LIST, WC_NONE,
 	0,
-	_nested_group_widgets, lengthof(_nested_group_widgets)
+	std::begin(_nested_group_widgets), std::end(_nested_group_widgets)
 );
 
 /**
diff --git a/src/highscore_gui.cpp b/src/highscore_gui.cpp
index ab6f3b3f52..4b55d65586 100644
--- a/src/highscore_gui.cpp
+++ b/src/highscore_gui.cpp
@@ -218,14 +218,14 @@ static WindowDesc _highscore_desc(
 	WDP_MANUAL, nullptr, 0, 0,
 	WC_HIGHSCORE, WC_NONE,
 	0,
-	_nested_highscore_widgets, lengthof(_nested_highscore_widgets)
+	std::begin(_nested_highscore_widgets), std::end(_nested_highscore_widgets)
 );
 
 static WindowDesc _endgame_desc(
 	WDP_MANUAL, nullptr, 0, 0,
 	WC_ENDSCREEN, WC_NONE,
 	0,
-	_nested_highscore_widgets, lengthof(_nested_highscore_widgets)
+	std::begin(_nested_highscore_widgets), std::end(_nested_highscore_widgets)
 );
 
 /**
diff --git a/src/industry_gui.cpp b/src/industry_gui.cpp
index cd72c4bc38..e68a6373d7 100644
--- a/src/industry_gui.cpp
+++ b/src/industry_gui.cpp
@@ -296,7 +296,7 @@ static WindowDesc _build_industry_desc(
 	WDP_AUTO, "build_industry", 170, 212,
 	WC_BUILD_INDUSTRY, WC_NONE,
 	WDF_CONSTRUCTION,
-	_nested_build_industry_widgets, lengthof(_nested_build_industry_widgets)
+	std::begin(_nested_build_industry_widgets), std::end(_nested_build_industry_widgets)
 );
 
 /** Build (fund or prospect) a new industry, */
@@ -1206,7 +1206,7 @@ static WindowDesc _industry_view_desc(
 	WDP_AUTO, "view_industry", 260, 120,
 	WC_INDUSTRY_VIEW, WC_NONE,
 	0,
-	_nested_industry_view_widgets, lengthof(_nested_industry_view_widgets)
+	std::begin(_nested_industry_view_widgets), std::end(_nested_industry_view_widgets)
 );
 
 void ShowIndustryViewWindow(int industry)
@@ -1867,7 +1867,7 @@ static WindowDesc _industry_directory_desc(
 	WDP_AUTO, "list_industries", 428, 190,
 	WC_INDUSTRY_DIRECTORY, WC_NONE,
 	0,
-	_nested_industry_directory_widgets, lengthof(_nested_industry_directory_widgets)
+	std::begin(_nested_industry_directory_widgets), std::end(_nested_industry_directory_widgets)
 );
 
 void ShowIndustryDirectory()
@@ -1905,7 +1905,7 @@ static WindowDesc _industry_cargoes_desc(
 	WDP_AUTO, "industry_cargoes", 300, 210,
 	WC_INDUSTRY_CARGOES, WC_NONE,
 	0,
-	_nested_industry_cargoes_widgets, lengthof(_nested_industry_cargoes_widgets)
+	std::begin(_nested_industry_cargoes_widgets), std::end(_nested_industry_cargoes_widgets)
 );
 
 /** Available types of field. */
diff --git a/src/intro_gui.cpp b/src/intro_gui.cpp
index 2c5acca26d..e5eef652f3 100644
--- a/src/intro_gui.cpp
+++ b/src/intro_gui.cpp
@@ -495,7 +495,7 @@ static WindowDesc _select_game_desc(
 	WDP_CENTER, nullptr, 0, 0,
 	WC_SELECT_GAME, WC_NONE,
 	WDF_NO_CLOSE,
-	_nested_select_game_widgets, lengthof(_nested_select_game_widgets)
+	std::begin(_nested_select_game_widgets), std::end(_nested_select_game_widgets)
 );
 
 void ShowSelectGameWindow()
diff --git a/src/league_gui.cpp b/src/league_gui.cpp
index 7a0b2c9b3b..f97a041604 100644
--- a/src/league_gui.cpp
+++ b/src/league_gui.cpp
@@ -200,7 +200,7 @@ static WindowDesc _performance_league_desc(
 	WDP_AUTO, "performance_league", 0, 0,
 	WC_COMPANY_LEAGUE, WC_NONE,
 	0,
-	_nested_performance_league_widgets, lengthof(_nested_performance_league_widgets)
+	std::begin(_nested_performance_league_widgets), std::end(_nested_performance_league_widgets)
 );
 
 void ShowPerformanceLeagueTable()
@@ -432,7 +432,7 @@ static WindowDesc _script_league_desc(
 	WDP_AUTO, "script_league", 0, 0,
 	WC_COMPANY_LEAGUE, WC_NONE,
 	0,
-	_nested_script_league_widgets, lengthof(_nested_script_league_widgets)
+	std::begin(_nested_script_league_widgets), std::end(_nested_script_league_widgets)
 );
 
 void ShowScriptLeagueTable(LeagueTableID table)
diff --git a/src/linkgraph/linkgraph_gui.cpp b/src/linkgraph/linkgraph_gui.cpp
index 4289389519..abe892d81c 100644
--- a/src/linkgraph/linkgraph_gui.cpp
+++ b/src/linkgraph/linkgraph_gui.cpp
@@ -541,7 +541,7 @@ static WindowDesc _linkgraph_legend_desc(
 	WDP_AUTO, "toolbar_linkgraph", 0, 0,
 	WC_LINKGRAPH_LEGEND, WC_NONE,
 	0,
-	_nested_linkgraph_legend_widgets, lengthof(_nested_linkgraph_legend_widgets)
+	std::begin(_nested_linkgraph_legend_widgets), std::end(_nested_linkgraph_legend_widgets)
 );
 
 /**
diff --git a/src/main_gui.cpp b/src/main_gui.cpp
index 05ec1a5de0..d27976bbcc 100644
--- a/src/main_gui.cpp
+++ b/src/main_gui.cpp
@@ -511,7 +511,7 @@ static WindowDesc _main_window_desc(
 	WDP_MANUAL, nullptr, 0, 0,
 	WC_MAIN_WINDOW, WC_NONE,
 	WDF_NO_CLOSE,
-	_nested_main_window_widgets, lengthof(_nested_main_window_widgets),
+	std::begin(_nested_main_window_widgets), std::end(_nested_main_window_widgets),
 	&MainWindow::hotkeys
 );
 
diff --git a/src/misc_gui.cpp b/src/misc_gui.cpp
index 9b6e894136..4a58104490 100644
--- a/src/misc_gui.cpp
+++ b/src/misc_gui.cpp
@@ -62,7 +62,7 @@ static WindowDesc _land_info_desc(
 	WDP_AUTO, nullptr, 0, 0,
 	WC_LAND_INFO, WC_NONE,
 	0,
-	_nested_land_info_widgets, lengthof(_nested_land_info_widgets)
+	std::begin(_nested_land_info_widgets), std::end(_nested_land_info_widgets)
 );
 
 class LandInfoWindow : public Window {
@@ -396,7 +396,7 @@ static WindowDesc _about_desc(
 	WDP_CENTER, nullptr, 0, 0,
 	WC_GAME_OPTIONS, WC_NONE,
 	0,
-	_nested_about_widgets, lengthof(_nested_about_widgets)
+	std::begin(_nested_about_widgets), std::end(_nested_about_widgets)
 );
 
 static const char * const _credits[] = {
@@ -654,7 +654,7 @@ static WindowDesc _tool_tips_desc(
 	WDP_MANUAL, nullptr, 0, 0, // Coordinates and sizes are not used,
 	WC_TOOLTIPS, WC_NONE,
 	WDF_NO_FOCUS | WDF_NO_CLOSE,
-	_nested_tooltips_widgets, lengthof(_nested_tooltips_widgets)
+	std::begin(_nested_tooltips_widgets), std::end(_nested_tooltips_widgets)
 );
 
 /** Window for displaying a tooltip. */
@@ -1067,7 +1067,7 @@ static WindowDesc _query_string_desc(
 	WDP_CENTER, nullptr, 0, 0,
 	WC_QUERY_STRING, WC_NONE,
 	0,
-	_nested_query_string_widgets, lengthof(_nested_query_string_widgets)
+	std::begin(_nested_query_string_widgets), std::end(_nested_query_string_widgets)
 );
 
 /**
@@ -1214,7 +1214,7 @@ static WindowDesc _query_desc(
 	WDP_CENTER, nullptr, 0, 0,
 	WC_CONFIRM_POPUP_QUERY, WC_NONE,
 	WDF_MODAL,
-	_nested_query_widgets, lengthof(_nested_query_widgets)
+	std::begin(_nested_query_widgets), std::end(_nested_query_widgets)
 );
 
 /**
diff --git a/src/music_gui.cpp b/src/music_gui.cpp
index 8cff204162..1f0d626377 100644
--- a/src/music_gui.cpp
+++ b/src/music_gui.cpp
@@ -645,7 +645,7 @@ static WindowDesc _music_track_selection_desc(
 	WDP_AUTO, nullptr, 0, 0,
 	WC_MUSIC_TRACK_SELECTION, WC_NONE,
 	0,
-	_nested_music_track_selection_widgets, lengthof(_nested_music_track_selection_widgets)
+	std::begin(_nested_music_track_selection_widgets), std::end(_nested_music_track_selection_widgets)
 );
 
 static void ShowMusicTrackSelection()
@@ -905,7 +905,7 @@ static WindowDesc _music_window_desc(
 	WDP_AUTO, "music", 0, 0,
 	WC_MUSIC_WINDOW, WC_NONE,
 	0,
-	_nested_music_window_widgets, lengthof(_nested_music_window_widgets)
+	std::begin(_nested_music_window_widgets), std::end(_nested_music_window_widgets)
 );
 
 void ShowMusicWindow()
diff --git a/src/network/network_chat_gui.cpp b/src/network/network_chat_gui.cpp
index c9f0835c62..c43b44172a 100644
--- a/src/network/network_chat_gui.cpp
+++ b/src/network/network_chat_gui.cpp
@@ -510,7 +510,7 @@ static WindowDesc _chat_window_desc(
 	WDP_MANUAL, nullptr, 0, 0,
 	WC_SEND_NETWORK_MSG, WC_NONE,
 	0,
-	_nested_chat_window_widgets, lengthof(_nested_chat_window_widgets)
+	std::begin(_nested_chat_window_widgets), std::end(_nested_chat_window_widgets)
 );
 
 
diff --git a/src/network/network_content_gui.cpp b/src/network/network_content_gui.cpp
index 4b752c62f7..2572b8a7b2 100644
--- a/src/network/network_content_gui.cpp
+++ b/src/network/network_content_gui.cpp
@@ -96,7 +96,7 @@ static WindowDesc _network_content_download_status_window_desc(
 	WDP_CENTER, nullptr, 0, 0,
 	WC_NETWORK_STATUS_WINDOW, WC_NONE,
 	WDF_MODAL,
-	_nested_network_content_download_status_window_widgets, lengthof(_nested_network_content_download_status_window_widgets)
+	std::begin(_nested_network_content_download_status_window_widgets), std::end(_nested_network_content_download_status_window_widgets)
 );
 
 BaseNetworkContentDownloadStatusWindow::BaseNetworkContentDownloadStatusWindow(WindowDesc *desc) :
@@ -1113,7 +1113,7 @@ static WindowDesc _network_content_list_desc(
 	WDP_CENTER, "list_content", 630, 460,
 	WC_NETWORK_WINDOW, WC_NONE,
 	0,
-	_nested_network_content_list_widgets, lengthof(_nested_network_content_list_widgets)
+	std::begin(_nested_network_content_list_widgets), std::end(_nested_network_content_list_widgets)
 );
 
 /**
diff --git a/src/network/network_gui.cpp b/src/network/network_gui.cpp
index 0f6c5e2dca..0270f60713 100644
--- a/src/network/network_gui.cpp
+++ b/src/network/network_gui.cpp
@@ -1007,7 +1007,7 @@ static WindowDesc _network_game_window_desc(
 	WDP_CENTER, "list_servers", 1000, 730,
 	WC_NETWORK_WINDOW, WC_NONE,
 	0,
-	_nested_network_game_widgets, lengthof(_nested_network_game_widgets)
+	std::begin(_nested_network_game_widgets), std::end(_nested_network_game_widgets)
 );
 
 void ShowNetworkGameWindow()
@@ -1280,7 +1280,7 @@ static WindowDesc _network_start_server_window_desc(
 	WDP_CENTER, nullptr, 0, 0,
 	WC_NETWORK_WINDOW, WC_NONE,
 	0,
-	_nested_network_start_server_window_widgets, lengthof(_nested_network_start_server_window_widgets)
+	std::begin(_nested_network_start_server_window_widgets), std::end(_nested_network_start_server_window_widgets)
 );
 
 static void ShowNetworkStartServerWindow()
@@ -1359,7 +1359,7 @@ static WindowDesc _client_list_desc(
 	WDP_AUTO, "list_clients", 220, 300,
 	WC_CLIENT_LIST, WC_NONE,
 	0,
-	_nested_client_list_widgets, lengthof(_nested_client_list_widgets)
+	std::begin(_nested_client_list_widgets), std::end(_nested_client_list_widgets)
 );
 
 /**
@@ -2274,7 +2274,7 @@ static WindowDesc _network_join_status_window_desc(
 	WDP_CENTER, nullptr, 0, 0,
 	WC_NETWORK_STATUS_WINDOW, WC_NONE,
 	WDF_MODAL,
-	_nested_network_join_status_window_widgets, lengthof(_nested_network_join_status_window_widgets)
+	std::begin(_nested_network_join_status_window_widgets), std::end(_nested_network_join_status_window_widgets)
 );
 
 void ShowJoinStatusWindow()
@@ -2396,7 +2396,7 @@ static WindowDesc _network_company_password_window_desc(
 	WDP_AUTO, nullptr, 0, 0,
 	WC_COMPANY_PASSWORD_WINDOW, WC_NONE,
 	0,
-	_nested_network_company_password_window_widgets, lengthof(_nested_network_company_password_window_widgets)
+	std::begin(_nested_network_company_password_window_widgets), std::end(_nested_network_company_password_window_widgets)
 );
 
 void ShowNetworkCompanyPasswordWindow(Window *parent)
@@ -2499,7 +2499,7 @@ static WindowDesc _network_ask_relay_desc(
 	WDP_CENTER, nullptr, 0, 0,
 	WC_NETWORK_ASK_RELAY, WC_NONE,
 	WDF_MODAL,
-	_nested_network_ask_relay_widgets, lengthof(_nested_network_ask_relay_widgets)
+	std::begin(_nested_network_ask_relay_widgets), std::end(_nested_network_ask_relay_widgets)
 );
 
 /**
@@ -2597,7 +2597,7 @@ static WindowDesc _network_ask_survey_desc(
 	WDP_CENTER, nullptr, 0, 0,
 	WC_NETWORK_ASK_SURVEY, WC_NONE,
 	WDF_MODAL,
-	_nested_network_ask_survey_widgets, lengthof(_nested_network_ask_survey_widgets)
+	std::begin(_nested_network_ask_survey_widgets), std::end(_nested_network_ask_survey_widgets)
 );
 
 /**
diff --git a/src/newgrf_debug_gui.cpp b/src/newgrf_debug_gui.cpp
index adfce85da9..afef4e9308 100644
--- a/src/newgrf_debug_gui.cpp
+++ b/src/newgrf_debug_gui.cpp
@@ -682,14 +682,14 @@ static WindowDesc _newgrf_inspect_chain_desc(
 	WDP_AUTO, "newgrf_inspect_chain", 400, 300,
 	WC_NEWGRF_INSPECT, WC_NONE,
 	0,
-	_nested_newgrf_inspect_chain_widgets, lengthof(_nested_newgrf_inspect_chain_widgets)
+	std::begin(_nested_newgrf_inspect_chain_widgets), std::end(_nested_newgrf_inspect_chain_widgets)
 );
 
 static WindowDesc _newgrf_inspect_desc(
 	WDP_AUTO, "newgrf_inspect", 400, 300,
 	WC_NEWGRF_INSPECT, WC_NONE,
 	0,
-	_nested_newgrf_inspect_widgets, lengthof(_nested_newgrf_inspect_widgets)
+	std::begin(_nested_newgrf_inspect_widgets), std::end(_nested_newgrf_inspect_widgets)
 );
 
 /**
@@ -1124,7 +1124,7 @@ static WindowDesc _sprite_aligner_desc(
 	WDP_AUTO, "sprite_aligner", 400, 300,
 	WC_SPRITE_ALIGNER, WC_NONE,
 	0,
-	_nested_sprite_aligner_widgets, lengthof(_nested_sprite_aligner_widgets)
+	std::begin(_nested_sprite_aligner_widgets), std::end(_nested_sprite_aligner_widgets)
 );
 
 /**
diff --git a/src/newgrf_gui.cpp b/src/newgrf_gui.cpp
index 375cc0572d..8036a3f629 100644
--- a/src/newgrf_gui.cpp
+++ b/src/newgrf_gui.cpp
@@ -541,7 +541,7 @@ static WindowDesc _newgrf_parameters_desc(
 	WDP_CENTER, "settings_newgrf_config", 500, 208,
 	WC_GRF_PARAMETERS, WC_NONE,
 	0,
-	_nested_newgrf_parameter_widgets, lengthof(_nested_newgrf_parameter_widgets)
+	std::begin(_nested_newgrf_parameter_widgets), std::end(_nested_newgrf_parameter_widgets)
 );
 
 static void OpenGRFParameterWindow(GRFConfig *c, bool editable)
@@ -1926,13 +1926,13 @@ static const NWidgetPart _nested_newgrf_infopanel_widgets[] = {
 /** Construct nested container widget for managing the lists and the info panel of the NewGRF GUI. */
 NWidgetBase* NewGRFDisplay(int *biggest_index)
 {
-	NWidgetBase *avs = MakeNWidgets(_nested_newgrf_availables_widgets, lengthof(_nested_newgrf_availables_widgets), biggest_index, nullptr);
+	NWidgetBase *avs = MakeNWidgets(std::begin(_nested_newgrf_availables_widgets), std::end(_nested_newgrf_availables_widgets), biggest_index, nullptr);
 
 	int biggest2;
-	NWidgetBase *acs = MakeNWidgets(_nested_newgrf_actives_widgets, lengthof(_nested_newgrf_actives_widgets), &biggest2, nullptr);
+	NWidgetBase *acs = MakeNWidgets(std::begin(_nested_newgrf_actives_widgets), std::end(_nested_newgrf_actives_widgets), &biggest2, nullptr);
 	*biggest_index = std::max(*biggest_index, biggest2);
 
-	NWidgetBase *inf = MakeNWidgets(_nested_newgrf_infopanel_widgets, lengthof(_nested_newgrf_infopanel_widgets), &biggest2, nullptr);
+	NWidgetBase *inf = MakeNWidgets(std::begin(_nested_newgrf_infopanel_widgets), std::end(_nested_newgrf_infopanel_widgets), &biggest2, nullptr);
 	*biggest_index = std::max(*biggest_index, biggest2);
 
 	return new NWidgetNewGRFDisplay(avs, acs, inf);
@@ -1960,7 +1960,7 @@ static WindowDesc _newgrf_desc(
 	WDP_CENTER, "settings_newgrf", 300, 263,
 	WC_GAME_OPTIONS, WC_NONE,
 	0,
-	_nested_newgrf_widgets, lengthof(_nested_newgrf_widgets)
+	std::begin(_nested_newgrf_widgets), std::end(_nested_newgrf_widgets)
 );
 
 /**
@@ -2044,7 +2044,7 @@ static WindowDesc _save_preset_desc(
 	WDP_CENTER, "save_preset", 140, 110,
 	WC_SAVE_PRESET, WC_GAME_OPTIONS,
 	WDF_MODAL,
-	_nested_save_preset_widgets, lengthof(_nested_save_preset_widgets)
+	std::begin(_nested_save_preset_widgets), std::end(_nested_save_preset_widgets)
 );
 
 /** Class for the save preset window. */
@@ -2189,7 +2189,7 @@ static WindowDesc _scan_progress_desc(
 	WDP_CENTER, nullptr, 0, 0,
 	WC_MODAL_PROGRESS, WC_NONE,
 	0,
-	_nested_scan_progress_widgets, lengthof(_nested_scan_progress_widgets)
+	std::begin(_nested_scan_progress_widgets), std::end(_nested_scan_progress_widgets)
 );
 
 /** Window for showing the progress of NewGRF scanning. */
diff --git a/src/news_gui.cpp b/src/news_gui.cpp
index 765983c47a..a3cc39b778 100644
--- a/src/news_gui.cpp
+++ b/src/news_gui.cpp
@@ -100,7 +100,7 @@ static WindowDesc _normal_news_desc(
 	WDP_MANUAL, nullptr, 0, 0,
 	WC_NEWS_WINDOW, WC_NONE,
 	0,
-	_nested_normal_news_widgets, lengthof(_nested_normal_news_widgets)
+	std::begin(_nested_normal_news_widgets), std::end(_nested_normal_news_widgets)
 );
 
 /* New vehicles news items. */
@@ -127,7 +127,7 @@ static WindowDesc _vehicle_news_desc(
 	WDP_MANUAL, nullptr, 0, 0,
 	WC_NEWS_WINDOW, WC_NONE,
 	0,
-	_nested_vehicle_news_widgets, lengthof(_nested_vehicle_news_widgets)
+	std::begin(_nested_vehicle_news_widgets), std::end(_nested_vehicle_news_widgets)
 );
 
 /* Company news items. */
@@ -155,7 +155,7 @@ static WindowDesc _company_news_desc(
 	WDP_MANUAL, nullptr, 0, 0,
 	WC_NEWS_WINDOW, WC_NONE,
 	0,
-	_nested_company_news_widgets, lengthof(_nested_company_news_widgets)
+	std::begin(_nested_company_news_widgets), std::end(_nested_company_news_widgets)
 );
 
 /* Thin news items. */
@@ -178,7 +178,7 @@ static WindowDesc _thin_news_desc(
 	WDP_MANUAL, nullptr, 0, 0,
 	WC_NEWS_WINDOW, WC_NONE,
 	0,
-	_nested_thin_news_widgets, lengthof(_nested_thin_news_widgets)
+	std::begin(_nested_thin_news_widgets), std::end(_nested_thin_news_widgets)
 );
 
 /* Small news items. */
@@ -204,7 +204,7 @@ static WindowDesc _small_news_desc(
 	WDP_MANUAL, nullptr, 0, 0,
 	WC_NEWS_WINDOW, WC_NONE,
 	0,
-	_nested_small_news_widgets, lengthof(_nested_small_news_widgets)
+	std::begin(_nested_small_news_widgets), std::end(_nested_small_news_widgets)
 );
 
 /**
@@ -1231,7 +1231,7 @@ static WindowDesc _message_history_desc(
 	WDP_AUTO, "list_news", 400, 140,
 	WC_MESSAGE_HISTORY, WC_NONE,
 	0,
-	_nested_message_history, lengthof(_nested_message_history)
+	std::begin(_nested_message_history), std::end(_nested_message_history)
 );
 
 /** Display window with news messages history */
diff --git a/src/object_gui.cpp b/src/object_gui.cpp
index f18e1660f1..f7f6fb8de7 100644
--- a/src/object_gui.cpp
+++ b/src/object_gui.cpp
@@ -720,7 +720,7 @@ static WindowDesc _build_object_desc(
 	WDP_AUTO, "build_object", 0, 0,
 	WC_BUILD_OBJECT, WC_BUILD_TOOLBAR,
 	WDF_CONSTRUCTION,
-	_nested_build_object_widgets, lengthof(_nested_build_object_widgets),
+	std::begin(_nested_build_object_widgets), std::end(_nested_build_object_widgets),
 	&BuildObjectWindow::hotkeys
 );
 
diff --git a/src/order_gui.cpp b/src/order_gui.cpp
index e3e84f21d5..61595f4391 100644
--- a/src/order_gui.cpp
+++ b/src/order_gui.cpp
@@ -1640,7 +1640,7 @@ static WindowDesc _orders_train_desc(
 	WDP_AUTO, "view_vehicle_orders_train", 384, 100,
 	WC_VEHICLE_ORDERS, WC_VEHICLE_VIEW,
 	WDF_CONSTRUCTION,
-	_nested_orders_train_widgets, lengthof(_nested_orders_train_widgets),
+	std::begin(_nested_orders_train_widgets), std::end(_nested_orders_train_widgets),
 	&OrdersWindow::hotkeys
 );
 
@@ -1713,7 +1713,7 @@ static WindowDesc _orders_desc(
 	WDP_AUTO, "view_vehicle_orders", 384, 100,
 	WC_VEHICLE_ORDERS, WC_VEHICLE_VIEW,
 	WDF_CONSTRUCTION,
-	_nested_orders_widgets, lengthof(_nested_orders_widgets),
+	std::begin(_nested_orders_widgets), std::end(_nested_orders_widgets),
 	&OrdersWindow::hotkeys
 );
 
@@ -1740,7 +1740,7 @@ static WindowDesc _other_orders_desc(
 	WDP_AUTO, "view_vehicle_orders_competitor", 384, 86,
 	WC_VEHICLE_ORDERS, WC_VEHICLE_VIEW,
 	WDF_CONSTRUCTION,
-	_nested_other_orders_widgets, lengthof(_nested_other_orders_widgets),
+	std::begin(_nested_other_orders_widgets), std::end(_nested_other_orders_widgets),
 	&OrdersWindow::hotkeys
 );
 
diff --git a/src/osk_gui.cpp b/src/osk_gui.cpp
index c43d319b75..6c189e343f 100644
--- a/src/osk_gui.cpp
+++ b/src/osk_gui.cpp
@@ -338,7 +338,7 @@ static WindowDesc _osk_desc(
 	WDP_CENTER, nullptr, 0, 0,
 	WC_OSK, WC_NONE,
 	0,
-	_nested_osk_widgets, lengthof(_nested_osk_widgets)
+	std::begin(_nested_osk_widgets), std::end(_nested_osk_widgets)
 );
 
 /**
diff --git a/src/rail_gui.cpp b/src/rail_gui.cpp
index e471cf6ec5..95c84b6d8d 100644
--- a/src/rail_gui.cpp
+++ b/src/rail_gui.cpp
@@ -841,7 +841,7 @@ static WindowDesc _build_rail_desc(
 	WDP_ALIGN_TOOLBAR, "toolbar_rail", 0, 0,
 	WC_BUILD_TOOLBAR, WC_NONE,
 	WDF_CONSTRUCTION,
-	_nested_build_rail_widgets, lengthof(_nested_build_rail_widgets),
+	std::begin(_nested_build_rail_widgets), std::end(_nested_build_rail_widgets),
 	&BuildRailToolbarWindow::hotkeys
 );
 
@@ -1631,7 +1631,7 @@ static WindowDesc _station_builder_desc(
 	WDP_AUTO, "build_station_rail", 350, 0,
 	WC_BUILD_STATION, WC_BUILD_TOOLBAR,
 	WDF_CONSTRUCTION,
-	_nested_station_builder_widgets, lengthof(_nested_station_builder_widgets),
+	std::begin(_nested_station_builder_widgets), std::end(_nested_station_builder_widgets),
 	&BuildRailStationWindow::hotkeys
 );
 
@@ -1889,7 +1889,7 @@ static WindowDesc _signal_builder_desc(
 	WDP_AUTO, nullptr, 0, 0,
 	WC_BUILD_SIGNAL, WC_BUILD_TOOLBAR,
 	WDF_CONSTRUCTION,
-	_nested_signal_builder_widgets, lengthof(_nested_signal_builder_widgets)
+	std::begin(_nested_signal_builder_widgets), std::end(_nested_signal_builder_widgets)
 );
 
 /**
@@ -1980,7 +1980,7 @@ static WindowDesc _build_depot_desc(
 	WDP_AUTO, nullptr, 0, 0,
 	WC_BUILD_DEPOT, WC_BUILD_TOOLBAR,
 	WDF_CONSTRUCTION,
-	_nested_build_depot_widgets, lengthof(_nested_build_depot_widgets)
+	std::begin(_nested_build_depot_widgets), std::end(_nested_build_depot_widgets)
 );
 
 static void ShowBuildTrainDepotPicker(Window *parent)
@@ -2208,7 +2208,7 @@ static WindowDesc _build_waypoint_desc(
 	WDP_AUTO, "build_waypoint", 0, 0,
 	WC_BUILD_WAYPOINT, WC_BUILD_TOOLBAR,
 	WDF_CONSTRUCTION,
-	_nested_build_waypoint_widgets, lengthof(_nested_build_waypoint_widgets)
+	std::begin(_nested_build_waypoint_widgets), std::end(_nested_build_waypoint_widgets)
 );
 
 static void ShowBuildWaypointPicker(Window *parent)
diff --git a/src/road_gui.cpp b/src/road_gui.cpp
index 056febcf00..5f5acde8d1 100644
--- a/src/road_gui.cpp
+++ b/src/road_gui.cpp
@@ -858,7 +858,7 @@ static WindowDesc _build_road_desc(
 	WDP_ALIGN_TOOLBAR, "toolbar_road", 0, 0,
 	WC_BUILD_TOOLBAR, WC_NONE,
 	WDF_CONSTRUCTION,
-	_nested_build_road_widgets, lengthof(_nested_build_road_widgets),
+	std::begin(_nested_build_road_widgets), std::end(_nested_build_road_widgets),
 	&BuildRoadToolbarWindow::road_hotkeys
 );
 
@@ -899,7 +899,7 @@ static WindowDesc _build_tramway_desc(
 	WDP_ALIGN_TOOLBAR, "toolbar_tramway", 0, 0,
 	WC_BUILD_TOOLBAR, WC_NONE,
 	WDF_CONSTRUCTION,
-	_nested_build_tramway_widgets, lengthof(_nested_build_tramway_widgets),
+	std::begin(_nested_build_tramway_widgets), std::end(_nested_build_tramway_widgets),
 	&BuildRoadToolbarWindow::tram_hotkeys
 );
 
@@ -954,7 +954,7 @@ static WindowDesc _build_road_scen_desc(
 	WDP_AUTO, "toolbar_road_scen", 0, 0,
 	WC_SCEN_BUILD_TOOLBAR, WC_NONE,
 	WDF_CONSTRUCTION,
-	_nested_build_road_scen_widgets, lengthof(_nested_build_road_scen_widgets),
+	std::begin(_nested_build_road_scen_widgets), std::end(_nested_build_road_scen_widgets),
 	&BuildRoadToolbarWindow::road_hotkeys
 );
 
@@ -989,7 +989,7 @@ static WindowDesc _build_tramway_scen_desc(
 	WDP_AUTO, "toolbar_tram_scen", 0, 0,
 	WC_SCEN_BUILD_TOOLBAR, WC_NONE,
 	WDF_CONSTRUCTION,
-	_nested_build_tramway_scen_widgets, lengthof(_nested_build_tramway_scen_widgets),
+	std::begin(_nested_build_tramway_scen_widgets), std::end(_nested_build_tramway_scen_widgets),
 	&BuildRoadToolbarWindow::tram_hotkeys
 );
 
@@ -1087,7 +1087,7 @@ static WindowDesc _build_road_depot_desc(
 	WDP_AUTO, nullptr, 0, 0,
 	WC_BUILD_DEPOT, WC_BUILD_TOOLBAR,
 	WDF_CONSTRUCTION,
-	_nested_build_road_depot_widgets, lengthof(_nested_build_road_depot_widgets)
+	std::begin(_nested_build_road_depot_widgets), std::end(_nested_build_road_depot_widgets)
 );
 
 static void ShowRoadDepotPicker(Window *parent)
@@ -1684,7 +1684,7 @@ static WindowDesc _road_station_picker_desc(
 	WDP_AUTO, "build_station_road", 0, 0,
 	WC_BUS_STATION, WC_BUILD_TOOLBAR,
 	WDF_CONSTRUCTION,
-	_nested_road_station_picker_widgets, lengthof(_nested_road_station_picker_widgets)
+	std::begin(_nested_road_station_picker_widgets), std::end(_nested_road_station_picker_widgets)
 );
 
 /** Widget definition of the build tram station window */
@@ -1769,7 +1769,7 @@ static WindowDesc _tram_station_picker_desc(
 	WDP_AUTO, "build_station_tram", 0, 0,
 	WC_BUS_STATION, WC_BUILD_TOOLBAR,
 	WDF_CONSTRUCTION,
-	_nested_tram_station_picker_widgets, lengthof(_nested_tram_station_picker_widgets)
+	std::begin(_nested_tram_station_picker_widgets), std::end(_nested_tram_station_picker_widgets)
 );
 
 static void ShowRVStationPicker(Window *parent, RoadStopType rs)
diff --git a/src/screenshot_gui.cpp b/src/screenshot_gui.cpp
index b6d68d0919..2ace881092 100644
--- a/src/screenshot_gui.cpp
+++ b/src/screenshot_gui.cpp
@@ -65,7 +65,7 @@ static WindowDesc _screenshot_window_desc(
 	WDP_AUTO, "take_a_screenshot", 200, 100,
 	WC_SCREENSHOT, WC_NONE,
 	0,
-	_nested_screenshot, lengthof(_nested_screenshot)
+	std::begin(_nested_screenshot), std::end(_nested_screenshot)
 );
 
 void ShowScreenshotWindow()
diff --git a/src/script/script_gui.cpp b/src/script/script_gui.cpp
index cb9c01b01f..90be17a5d5 100644
--- a/src/script/script_gui.cpp
+++ b/src/script/script_gui.cpp
@@ -265,7 +265,7 @@ static WindowDesc _script_list_desc(
 	WDP_CENTER, "settings_script_list", 200, 234,
 	WC_SCRIPT_LIST, WC_NONE,
 	0,
-	_nested_script_list_widgets, lengthof(_nested_script_list_widgets)
+	std::begin(_nested_script_list_widgets), std::end(_nested_script_list_widgets)
 );
 
 /**
@@ -608,7 +608,7 @@ static WindowDesc _script_settings_desc(
 	WDP_CENTER, "settings_script", 500, 208,
 	WC_SCRIPT_SETTINGS, WC_NONE,
 	0,
-	_nested_script_settings_widgets, lengthof(_nested_script_settings_widgets)
+	std::begin(_nested_script_settings_widgets), std::end(_nested_script_settings_widgets)
 );
 
 /**
@@ -1195,7 +1195,7 @@ static WindowDesc _script_debug_desc(
 	WDP_AUTO, "script_debug", 600, 450,
 	WC_SCRIPT_DEBUG, WC_NONE,
 	0,
-	_nested_script_debug_widgets, lengthof(_nested_script_debug_widgets),
+	std::begin(_nested_script_debug_widgets), std::end(_nested_script_debug_widgets),
 	&ScriptDebugWindow::hotkeys
 );
 
diff --git a/src/settings_gui.cpp b/src/settings_gui.cpp
index 2f1fedf05d..140b3765e7 100644
--- a/src/settings_gui.cpp
+++ b/src/settings_gui.cpp
@@ -925,7 +925,7 @@ static WindowDesc _game_options_desc(
 	WDP_CENTER, nullptr, 0, 0,
 	WC_GAME_OPTIONS, WC_NONE,
 	0,
-	_nested_game_options_widgets, lengthof(_nested_game_options_widgets)
+	std::begin(_nested_game_options_widgets), std::end(_nested_game_options_widgets)
 );
 
 /** Open the game options window. */
@@ -2657,7 +2657,7 @@ static WindowDesc _settings_selection_desc(
 	WDP_CENTER, "settings", 510, 450,
 	WC_GAME_OPTIONS, WC_NONE,
 	0,
-	_nested_settings_selection_widgets, lengthof(_nested_settings_selection_widgets)
+	std::begin(_nested_settings_selection_widgets), std::end(_nested_settings_selection_widgets)
 );
 
 /** Open advanced settings window. */
@@ -2956,7 +2956,7 @@ static WindowDesc _cust_currency_desc(
 	WDP_CENTER, nullptr, 0, 0,
 	WC_CUSTOM_CURRENCY, WC_NONE,
 	0,
-	_nested_cust_currency_widgets, lengthof(_nested_cust_currency_widgets)
+	std::begin(_nested_cust_currency_widgets), std::end(_nested_cust_currency_widgets)
 );
 
 /** Open custom currency window. */
diff --git a/src/signs_gui.cpp b/src/signs_gui.cpp
index 94a2d2fc9a..e3c9cd84ea 100644
--- a/src/signs_gui.cpp
+++ b/src/signs_gui.cpp
@@ -389,7 +389,7 @@ static WindowDesc _sign_list_desc(
 	WDP_AUTO, "list_signs", 358, 138,
 	WC_SIGN_LIST, WC_NONE,
 	0,
-	_nested_sign_list_widgets, lengthof(_nested_sign_list_widgets),
+	std::begin(_nested_sign_list_widgets), std::end(_nested_sign_list_widgets),
 	&SignListWindow::hotkeys
 );
 
@@ -555,7 +555,7 @@ static WindowDesc _query_sign_edit_desc(
 	WDP_CENTER, nullptr, 0, 0,
 	WC_QUERY_STRING, WC_NONE,
 	WDF_CONSTRUCTION,
-	_nested_query_sign_edit_widgets, lengthof(_nested_query_sign_edit_widgets)
+	std::begin(_nested_query_sign_edit_widgets), std::end(_nested_query_sign_edit_widgets)
 );
 
 /**
diff --git a/src/smallmap_gui.cpp b/src/smallmap_gui.cpp
index c928f08b52..4e17c1f55d 100644
--- a/src/smallmap_gui.cpp
+++ b/src/smallmap_gui.cpp
@@ -1833,8 +1833,8 @@ static NWidgetBase *SmallMapDisplay(int *biggest_index)
 {
 	NWidgetContainer *map_display = new NWidgetSmallmapDisplay;
 
-	MakeNWidgets(_nested_smallmap_display, lengthof(_nested_smallmap_display), biggest_index, map_display);
-	MakeNWidgets(_nested_smallmap_bar, lengthof(_nested_smallmap_bar), biggest_index, map_display);
+	MakeNWidgets(std::begin(_nested_smallmap_display), std::end(_nested_smallmap_display), biggest_index, map_display);
+	MakeNWidgets(std::begin(_nested_smallmap_bar), std::end(_nested_smallmap_bar), biggest_index, map_display);
 	return map_display;
 }
 
@@ -1869,7 +1869,7 @@ static WindowDesc _smallmap_desc(
 	WDP_AUTO, "smallmap", 484, 314,
 	WC_SMALLMAP, WC_NONE,
 	0,
-	_nested_smallmap_widgets, lengthof(_nested_smallmap_widgets)
+	std::begin(_nested_smallmap_widgets), std::end(_nested_smallmap_widgets)
 );
 
 /**
diff --git a/src/station_gui.cpp b/src/station_gui.cpp
index 941d309494..fcff2b1e25 100644
--- a/src/station_gui.cpp
+++ b/src/station_gui.cpp
@@ -765,7 +765,7 @@ static WindowDesc _company_stations_desc(
 	WDP_AUTO, "list_stations", 358, 162,
 	WC_STATION_LIST, WC_NONE,
 	0,
-	_nested_company_stations_widgets, lengthof(_nested_company_stations_widgets)
+	std::begin(_nested_company_stations_widgets), std::end(_nested_company_stations_widgets)
 );
 
 /**
@@ -2121,7 +2121,7 @@ static WindowDesc _station_view_desc(
 	WDP_AUTO, "view_station", 249, 117,
 	WC_STATION_VIEW, WC_NONE,
 	0,
-	_nested_station_view_widgets, lengthof(_nested_station_view_widgets)
+	std::begin(_nested_station_view_widgets), std::end(_nested_station_view_widgets)
 );
 
 /**
@@ -2378,7 +2378,7 @@ static WindowDesc _select_station_desc(
 	WDP_AUTO, "build_station_join", 200, 180,
 	WC_SELECT_STATION, WC_NONE,
 	WDF_CONSTRUCTION,
-	_nested_select_station_widgets, lengthof(_nested_select_station_widgets)
+	std::begin(_nested_select_station_widgets), std::end(_nested_select_station_widgets)
 );
 
 
diff --git a/src/statusbar_gui.cpp b/src/statusbar_gui.cpp
index 848b7ee6b0..be49e19854 100644
--- a/src/statusbar_gui.cpp
+++ b/src/statusbar_gui.cpp
@@ -231,7 +231,7 @@ static WindowDesc _main_status_desc(
 	WDP_MANUAL, nullptr, 0, 0,
 	WC_STATUS_BAR, WC_NONE,
 	WDF_NO_FOCUS | WDF_NO_CLOSE,
-	_nested_main_status_widgets, lengthof(_nested_main_status_widgets)
+	std::begin(_nested_main_status_widgets), std::end(_nested_main_status_widgets)
 );
 
 /**
diff --git a/src/story_gui.cpp b/src/story_gui.cpp
index 3ed03149c7..9f3db43d1b 100644
--- a/src/story_gui.cpp
+++ b/src/story_gui.cpp
@@ -972,7 +972,7 @@ static WindowDesc _story_book_desc(
 	WDP_CENTER, "view_story", 400, 300,
 	WC_STORY_BOOK, WC_NONE,
 	0,
-	_nested_story_book_widgets, lengthof(_nested_story_book_widgets)
+	std::begin(_nested_story_book_widgets), std::end(_nested_story_book_widgets)
 );
 
 static CursorID TranslateStoryPageButtonCursor(StoryPageButtonCursor cursor)
diff --git a/src/subsidy_gui.cpp b/src/subsidy_gui.cpp
index d19c6e750d..ff6efbc651 100644
--- a/src/subsidy_gui.cpp
+++ b/src/subsidy_gui.cpp
@@ -238,7 +238,7 @@ static WindowDesc _subsidies_list_desc(
 	WDP_AUTO, "list_subsidies", 500, 127,
 	WC_SUBSIDIES_LIST, WC_NONE,
 	0,
-	_nested_subsidies_list_widgets, lengthof(_nested_subsidies_list_widgets)
+	std::begin(_nested_subsidies_list_widgets), std::end(_nested_subsidies_list_widgets)
 );
 
 
diff --git a/src/terraform_gui.cpp b/src/terraform_gui.cpp
index ee7a353e58..d24cbcc5d4 100644
--- a/src/terraform_gui.cpp
+++ b/src/terraform_gui.cpp
@@ -355,7 +355,7 @@ static WindowDesc _terraform_desc(
 	WDP_MANUAL, "toolbar_landscape", 0, 0,
 	WC_SCEN_LAND_GEN, WC_NONE,
 	WDF_CONSTRUCTION,
-	_nested_terraform_widgets, lengthof(_nested_terraform_widgets),
+	std::begin(_nested_terraform_widgets), std::end(_nested_terraform_widgets),
 	&TerraformToolbarWindow::hotkeys
 );
 
@@ -743,7 +743,7 @@ static WindowDesc _scen_edit_land_gen_desc(
 	WDP_AUTO, "toolbar_landscape_scen", 0, 0,
 	WC_SCEN_LAND_GEN, WC_NONE,
 	WDF_CONSTRUCTION,
-	_nested_scen_edit_land_gen_widgets, lengthof(_nested_scen_edit_land_gen_widgets),
+	std::begin(_nested_scen_edit_land_gen_widgets), std::end(_nested_scen_edit_land_gen_widgets),
 	&ScenarioEditorLandscapeGenerationWindow::hotkeys
 );
 
diff --git a/src/textfile_gui.cpp b/src/textfile_gui.cpp
index 210cdb3070..37bf6653f2 100644
--- a/src/textfile_gui.cpp
+++ b/src/textfile_gui.cpp
@@ -56,7 +56,7 @@ static WindowDesc _textfile_desc(
 	WDP_CENTER, "textfile", 630, 460,
 	WC_TEXTFILE, WC_NONE,
 	0,
-	_nested_textfile_widgets, lengthof(_nested_textfile_widgets)
+	std::begin(_nested_textfile_widgets), std::end(_nested_textfile_widgets)
 );
 
 TextfileWindow::TextfileWindow(TextfileType file_type) : Window(&_textfile_desc), file_type(file_type)
diff --git a/src/timetable_gui.cpp b/src/timetable_gui.cpp
index 80b49a24f0..e58375d64d 100644
--- a/src/timetable_gui.cpp
+++ b/src/timetable_gui.cpp
@@ -746,7 +746,7 @@ static WindowDesc _timetable_desc(
 	WDP_AUTO, "view_vehicle_timetable", 400, 130,
 	WC_VEHICLE_TIMETABLE, WC_VEHICLE_VIEW,
 	WDF_CONSTRUCTION,
-	_nested_timetable_widgets, lengthof(_nested_timetable_widgets)
+	std::begin(_nested_timetable_widgets), std::end(_nested_timetable_widgets)
 );
 
 /**
diff --git a/src/toolbar_gui.cpp b/src/toolbar_gui.cpp
index f7f7eccdc1..91c2def043 100644
--- a/src/toolbar_gui.cpp
+++ b/src/toolbar_gui.cpp
@@ -2254,7 +2254,7 @@ static WindowDesc _toolb_normal_desc(
 	WDP_MANUAL, nullptr, 0, 0,
 	WC_MAIN_TOOLBAR, WC_NONE,
 	WDF_NO_FOCUS | WDF_NO_CLOSE,
-	_nested_toolbar_normal_widgets, lengthof(_nested_toolbar_normal_widgets),
+	std::begin(_nested_toolbar_normal_widgets), std::end(_nested_toolbar_normal_widgets),
 	&MainToolbarWindow::hotkeys
 );
 
@@ -2583,7 +2583,7 @@ static const NWidgetPart _nested_toolb_scen_inner_widgets[] = {
 
 static NWidgetBase *MakeScenarioToolbar(int *biggest_index)
 {
-	return MakeNWidgets(_nested_toolb_scen_inner_widgets, lengthof(_nested_toolb_scen_inner_widgets), biggest_index, new NWidgetScenarioToolbarContainer());
+	return MakeNWidgets(std::begin(_nested_toolb_scen_inner_widgets), std::end(_nested_toolb_scen_inner_widgets), biggest_index, new NWidgetScenarioToolbarContainer());
 }
 
 static const NWidgetPart _nested_toolb_scen_widgets[] = {
@@ -2594,7 +2594,7 @@ static WindowDesc _toolb_scen_desc(
 	WDP_MANUAL, nullptr, 0, 0,
 	WC_MAIN_TOOLBAR, WC_NONE,
 	WDF_NO_FOCUS | WDF_NO_CLOSE,
-	_nested_toolb_scen_widgets, lengthof(_nested_toolb_scen_widgets),
+	std::begin(_nested_toolb_scen_widgets), std::end(_nested_toolb_scen_widgets),
 	&ScenarioEditorToolbarWindow::hotkeys
 );
 
diff --git a/src/town_gui.cpp b/src/town_gui.cpp
index 15c1be5b27..8b2a820f57 100644
--- a/src/town_gui.cpp
+++ b/src/town_gui.cpp
@@ -330,7 +330,7 @@ static WindowDesc _town_authority_desc(
 	WDP_AUTO, "view_town_authority", 317, 222,
 	WC_TOWN_AUTHORITY, WC_NONE,
 	0,
-	_nested_town_authority_widgets, lengthof(_nested_town_authority_widgets)
+	std::begin(_nested_town_authority_widgets), std::end(_nested_town_authority_widgets)
 );
 
 static void ShowTownAuthorityWindow(uint town)
@@ -631,7 +631,7 @@ static WindowDesc _town_game_view_desc(
 	WDP_AUTO, "view_town", 260, TownViewWindow::WID_TV_HEIGHT_NORMAL,
 	WC_TOWN_VIEW, WC_NONE,
 	0,
-	_nested_town_game_view_widgets, lengthof(_nested_town_game_view_widgets)
+	std::begin(_nested_town_game_view_widgets), std::end(_nested_town_game_view_widgets)
 );
 
 static const NWidgetPart _nested_town_editor_view_widgets[] = {
@@ -662,7 +662,7 @@ static WindowDesc _town_editor_view_desc(
 	WDP_AUTO, "view_town_scen", 260, TownViewWindow::WID_TV_HEIGHT_NORMAL,
 	WC_TOWN_VIEW, WC_NONE,
 	0,
-	_nested_town_editor_view_widgets, lengthof(_nested_town_editor_view_widgets)
+	std::begin(_nested_town_editor_view_widgets), std::end(_nested_town_editor_view_widgets)
 );
 
 void ShowTownViewWindow(TownID town)
@@ -1037,7 +1037,7 @@ static WindowDesc _town_directory_desc(
 	WDP_AUTO, "list_towns", 208, 202,
 	WC_TOWN_DIRECTORY, WC_NONE,
 	0,
-	_nested_town_directory_widgets, lengthof(_nested_town_directory_widgets)
+	std::begin(_nested_town_directory_widgets), std::end(_nested_town_directory_widgets)
 );
 
 void ShowTownDirectory()
@@ -1287,7 +1287,7 @@ static WindowDesc _found_town_desc(
 	WDP_AUTO, "build_town", 160, 162,
 	WC_FOUND_TOWN, WC_NONE,
 	WDF_CONSTRUCTION,
-	_nested_found_town_widgets, lengthof(_nested_found_town_widgets)
+	std::begin(_nested_found_town_widgets), std::end(_nested_found_town_widgets)
 );
 
 void ShowFoundTownWindow()
diff --git a/src/transparency_gui.cpp b/src/transparency_gui.cpp
index 8c11803f07..6d998de96b 100644
--- a/src/transparency_gui.cpp
+++ b/src/transparency_gui.cpp
@@ -152,7 +152,7 @@ static WindowDesc _transparency_desc(
 	WDP_MANUAL, "toolbar_transparency", 0, 0,
 	WC_TRANSPARENCY_TOOLBAR, WC_NONE,
 	0,
-	_nested_transparency_widgets, lengthof(_nested_transparency_widgets)
+	std::begin(_nested_transparency_widgets), std::end(_nested_transparency_widgets)
 );
 
 /**
diff --git a/src/tree_gui.cpp b/src/tree_gui.cpp
index ac8d0fc962..fb39ab7fd7 100644
--- a/src/tree_gui.cpp
+++ b/src/tree_gui.cpp
@@ -320,7 +320,7 @@ static WindowDesc _build_trees_desc(
 	WDP_AUTO, "build_tree", 0, 0,
 	WC_BUILD_TREES, WC_NONE,
 	WDF_CONSTRUCTION,
-	_nested_build_trees_widgets, lengthof(_nested_build_trees_widgets)
+	std::begin(_nested_build_trees_widgets), std::end(_nested_build_trees_widgets)
 );
 
 void ShowBuildTreesToolbar()
diff --git a/src/vehicle_gui.cpp b/src/vehicle_gui.cpp
index 9810c9c17f..71250a5d1e 100644
--- a/src/vehicle_gui.cpp
+++ b/src/vehicle_gui.cpp
@@ -1238,7 +1238,7 @@ static WindowDesc _vehicle_refit_desc(
 	WDP_AUTO, "view_vehicle_refit", 240, 174,
 	WC_VEHICLE_REFIT, WC_VEHICLE_VIEW,
 	WDF_CONSTRUCTION,
-	_nested_vehicle_refit_widgets, lengthof(_nested_vehicle_refit_widgets)
+	std::begin(_nested_vehicle_refit_widgets), std::end(_nested_vehicle_refit_widgets)
 );
 
 /**
@@ -2171,14 +2171,14 @@ static WindowDesc _vehicle_list_other_desc(
 	WDP_AUTO, "list_vehicles", 260, 246,
 	WC_INVALID, WC_NONE,
 	0,
-	_nested_vehicle_list, lengthof(_nested_vehicle_list)
+	std::begin(_nested_vehicle_list), std::end(_nested_vehicle_list)
 );
 
 static WindowDesc _vehicle_list_train_desc(
 	WDP_AUTO, "list_vehicles_train", 325, 246,
 	WC_TRAINS_LIST, WC_NONE,
 	0,
-	_nested_vehicle_list, lengthof(_nested_vehicle_list)
+	std::begin(_nested_vehicle_list), std::end(_nested_vehicle_list)
 );
 
 static void ShowVehicleListWindowLocal(CompanyID company, VehicleListType vlt, VehicleType vehicle_type, uint32_t unique_number)
@@ -2680,7 +2680,7 @@ static WindowDesc _train_vehicle_details_desc(
 	WDP_AUTO, "view_vehicle_details_train", 405, 178,
 	WC_VEHICLE_DETAILS, WC_VEHICLE_VIEW,
 	0,
-	_nested_train_vehicle_details_widgets, lengthof(_nested_train_vehicle_details_widgets)
+	std::begin(_nested_train_vehicle_details_widgets), std::end(_nested_train_vehicle_details_widgets)
 );
 
 /** Vehicle details window descriptor for other vehicles than a train. */
@@ -2688,7 +2688,7 @@ static WindowDesc _nontrain_vehicle_details_desc(
 	WDP_AUTO, "view_vehicle_details", 405, 113,
 	WC_VEHICLE_DETAILS, WC_VEHICLE_VIEW,
 	0,
-	_nested_nontrain_vehicle_details_widgets, lengthof(_nested_nontrain_vehicle_details_widgets)
+	std::begin(_nested_nontrain_vehicle_details_widgets), std::end(_nested_nontrain_vehicle_details_widgets)
 );
 
 /** Shows the vehicle details window of the given vehicle. */
@@ -3285,7 +3285,7 @@ static WindowDesc _vehicle_view_desc(
 	WDP_AUTO, "view_vehicle", 250, 116,
 	WC_VEHICLE_VIEW, WC_NONE,
 	0,
-	_nested_vehicle_view_widgets, lengthof(_nested_vehicle_view_widgets),
+	std::begin(_nested_vehicle_view_widgets), std::end(_nested_vehicle_view_widgets),
 	&VehicleViewWindow::hotkeys
 );
 
@@ -3297,7 +3297,7 @@ static WindowDesc _train_view_desc(
 	WDP_AUTO, "view_vehicle_train", 250, 134,
 	WC_VEHICLE_VIEW, WC_NONE,
 	0,
-	_nested_vehicle_view_widgets, lengthof(_nested_vehicle_view_widgets),
+	std::begin(_nested_vehicle_view_widgets), std::end(_nested_vehicle_view_widgets),
 	&VehicleViewWindow::hotkeys
 );
 
diff --git a/src/viewport_gui.cpp b/src/viewport_gui.cpp
index c8bf96157b..c81e4920f6 100644
--- a/src/viewport_gui.cpp
+++ b/src/viewport_gui.cpp
@@ -163,7 +163,7 @@ static WindowDesc _extra_viewport_desc(
 	WDP_AUTO, "extra_viewport", 300, 268,
 	WC_EXTRA_VIEWPORT, WC_NONE,
 	0,
-	_nested_extra_viewport_widgets, lengthof(_nested_extra_viewport_widgets)
+	std::begin(_nested_extra_viewport_widgets), std::end(_nested_extra_viewport_widgets)
 );
 
 /**
diff --git a/src/waypoint_gui.cpp b/src/waypoint_gui.cpp
index d8b3c10379..d2042cf90e 100644
--- a/src/waypoint_gui.cpp
+++ b/src/waypoint_gui.cpp
@@ -187,7 +187,7 @@ static WindowDesc _waypoint_view_desc(
 	WDP_AUTO, "view_waypoint", 260, 118,
 	WC_WAYPOINT_VIEW, WC_NONE,
 	0,
-	_nested_waypoint_view_widgets, lengthof(_nested_waypoint_view_widgets)
+	std::begin(_nested_waypoint_view_widgets), std::end(_nested_waypoint_view_widgets)
 );
 
 /**
diff --git a/src/widget.cpp b/src/widget.cpp
index 5d2687f97a..9eabaa8a3c 100644
--- a/src/widget.cpp
+++ b/src/widget.cpp
@@ -3008,23 +3008,23 @@ bool NWidgetLeaf::ButtonHit(const Point &pt)
  * settings that follow it, until encountering a #EndContainer, another
  * #NWidget, or the end of the parts array.
  *
- * @param parts Array with parts of the nested widget.
- * @param count Length of the \a parts array.
+ * @param nwid_begin Pointer to beginning of nested widget parts.
+ * @param nwid_end Pointer to ending of nested widget parts.
  * @param dest  Address of pointer to use for returning the composed widget.
  * @param fill_dest Fill the composed widget with child widgets.
  * @param biggest_index Pointer to biggest nested widget index in the tree encountered so far.
  * @return Number of widget part elements used to compose the widget.
  * @pre \c biggest_index != nullptr.
  */
-static int MakeNWidget(const NWidgetPart *parts, int count, NWidgetBase **dest, bool *fill_dest, int *biggest_index)
+static int MakeNWidget(const NWidgetPart *nwid_begin, const NWidgetPart *nwid_end, NWidgetBase **dest, bool *fill_dest, int *biggest_index)
 {
 	int num_used = 0;
 
 	*dest = nullptr;
 	*fill_dest = false;
 
-	while (count > num_used) {
-		switch (parts->type) {
+	while (nwid_begin < nwid_end) {
+		switch (nwid_begin->type) {
 			case NWID_SPACER:
 				if (*dest != nullptr) return num_used;
 				*dest = new NWidgetSpacer(0, 0);
@@ -3032,13 +3032,13 @@ static int MakeNWidget(const NWidgetPart *parts, int count, NWidgetBase **dest,
 
 			case NWID_HORIZONTAL:
 				if (*dest != nullptr) return num_used;
-				*dest = new NWidgetHorizontal(parts->u.cont_flags);
+				*dest = new NWidgetHorizontal(nwid_begin->u.cont_flags);
 				*fill_dest = true;
 				break;
 
 			case NWID_HORIZONTAL_LTR:
 				if (*dest != nullptr) return num_used;
-				*dest = new NWidgetHorizontalLTR(parts->u.cont_flags);
+				*dest = new NWidgetHorizontalLTR(nwid_begin->u.cont_flags);
 				*fill_dest = true;
 				break;
 
@@ -3046,14 +3046,14 @@ static int MakeNWidget(const NWidgetPart *parts, int count, NWidgetBase **dest,
 			case WWT_INSET:
 			case WWT_FRAME:
 				if (*dest != nullptr) return num_used;
-				*dest = new NWidgetBackground(parts->type, parts->u.widget.colour, parts->u.widget.index);
-				*biggest_index = std::max(*biggest_index, (int)parts->u.widget.index);
+				*dest = new NWidgetBackground(nwid_begin->type, nwid_begin->u.widget.colour, nwid_begin->u.widget.index);
+				*biggest_index = std::max(*biggest_index, (int)nwid_begin->u.widget.index);
 				*fill_dest = true;
 				break;
 
 			case NWID_VERTICAL:
 				if (*dest != nullptr) return num_used;
-				*dest = new NWidgetVertical(parts->u.cont_flags);
+				*dest = new NWidgetVertical(nwid_begin->u.cont_flags);
 				*fill_dest = true;
 				break;
 
@@ -3062,9 +3062,9 @@ static int MakeNWidget(const NWidgetPart *parts, int count, NWidgetBase **dest,
 				NWidgetMatrix *nwm = new NWidgetMatrix();
 				*dest = nwm;
 				*fill_dest = true;
-				nwm->SetIndex(parts->u.widget.index);
-				nwm->SetColour(parts->u.widget.colour);
-				*biggest_index = std::max(*biggest_index, (int)parts->u.widget.index);
+				nwm->SetIndex(nwid_begin->u.widget.index);
+				nwm->SetColour(nwid_begin->u.widget.colour);
+				*biggest_index = std::max(*biggest_index, (int)nwid_begin->u.widget.index);
 				break;
 			}
 
@@ -3072,7 +3072,7 @@ static int MakeNWidget(const NWidgetPart *parts, int count, NWidgetBase **dest,
 				if (*dest != nullptr) return num_used;
 				/* Ensure proper functioning even when the called code simply writes its largest index. */
 				int biggest = -1;
-				*dest = parts->u.func_ptr(&biggest);
+				*dest = nwid_begin->u.func_ptr(&biggest);
 				*biggest_index = std::max(*biggest_index, biggest);
 				*fill_dest = false;
 				break;
@@ -3081,8 +3081,8 @@ static int MakeNWidget(const NWidgetPart *parts, int count, NWidgetBase **dest,
 			case WPT_RESIZE: {
 				NWidgetResizeBase *nwrb = dynamic_cast<NWidgetResizeBase *>(*dest);
 				if (nwrb != nullptr) {
-					assert(parts->u.xy.x >= 0 && parts->u.xy.y >= 0);
-					nwrb->SetResize(parts->u.xy.x, parts->u.xy.y);
+					assert(nwid_begin->u.xy.x >= 0 && nwid_begin->u.xy.y >= 0);
+					nwrb->SetResize(nwid_begin->u.xy.x, nwid_begin->u.xy.y);
 				}
 				break;
 			}
@@ -3090,8 +3090,8 @@ static int MakeNWidget(const NWidgetPart *parts, int count, NWidgetBase **dest,
 			case WPT_MINSIZE: {
 				NWidgetResizeBase *nwrb = dynamic_cast<NWidgetResizeBase *>(*dest);
 				if (nwrb != nullptr) {
-					assert(parts->u.xy.x >= 0 && parts->u.xy.y >= 0);
-					nwrb->SetMinimalSize(parts->u.xy.x, parts->u.xy.y);
+					assert(nwid_begin->u.xy.x >= 0 && nwid_begin->u.xy.y >= 0);
+					nwrb->SetMinimalSize(nwid_begin->u.xy.x, nwid_begin->u.xy.y);
 				}
 				break;
 			}
@@ -3099,8 +3099,8 @@ static int MakeNWidget(const NWidgetPart *parts, int count, NWidgetBase **dest,
 			case WPT_MINTEXTLINES: {
 				NWidgetResizeBase *nwrb = dynamic_cast<NWidgetResizeBase *>(*dest);
 				if (nwrb != nullptr) {
-					assert(parts->u.text_lines.size >= FS_BEGIN && parts->u.text_lines.size < FS_END);
-					nwrb->SetMinimalTextLines(parts->u.text_lines.lines, parts->u.text_lines.spacing, parts->u.text_lines.size);
+					assert(nwid_begin->u.text_lines.size >= FS_BEGIN && nwid_begin->u.text_lines.size < FS_END);
+					nwrb->SetMinimalTextLines(nwid_begin->u.text_lines.lines, nwid_begin->u.text_lines.spacing, nwid_begin->u.text_lines.size);
 				}
 				break;
 			}
@@ -3108,7 +3108,7 @@ static int MakeNWidget(const NWidgetPart *parts, int count, NWidgetBase **dest,
 			case WPT_TEXTSTYLE: {
 				NWidgetCore *nwc = dynamic_cast<NWidgetCore *>(*dest);
 				if (nwc != nullptr) {
-					nwc->SetTextStyle(parts->u.text_style.colour, parts->u.text_style.size);
+					nwc->SetTextStyle(nwid_begin->u.text_style.colour, nwid_begin->u.text_style.size);
 				}
 				break;
 			}
@@ -3116,43 +3116,43 @@ static int MakeNWidget(const NWidgetPart *parts, int count, NWidgetBase **dest,
 			case WPT_ALIGNMENT: {
 				NWidgetCore *nwc = dynamic_cast<NWidgetCore *>(*dest);
 				if (nwc != nullptr) {
-					nwc->SetAlignment(parts->u.align.align);
+					nwc->SetAlignment(nwid_begin->u.align.align);
 				}
 				break;
 			}
 
 			case WPT_FILL: {
 				NWidgetResizeBase *nwrb = dynamic_cast<NWidgetResizeBase *>(*dest);
-				if (nwrb != nullptr) nwrb->SetFill(parts->u.xy.x, parts->u.xy.y);
+				if (nwrb != nullptr) nwrb->SetFill(nwid_begin->u.xy.x, nwid_begin->u.xy.y);
 				break;
 			}
 
 			case WPT_DATATIP: {
 				NWidgetCore *nwc = dynamic_cast<NWidgetCore *>(*dest);
 				if (nwc != nullptr) {
-					nwc->widget_data = parts->u.data_tip.data;
-					nwc->tool_tip = parts->u.data_tip.tooltip;
+					nwc->widget_data = nwid_begin->u.data_tip.data;
+					nwc->tool_tip = nwid_begin->u.data_tip.tooltip;
 				}
 				break;
 			}
 
 			case WPT_PADDING:
-				if (*dest != nullptr) (*dest)->SetPadding(parts->u.padding);
+				if (*dest != nullptr) (*dest)->SetPadding(nwid_begin->u.padding);
 				break;
 
 			case WPT_PIPSPACE: {
 				NWidgetPIPContainer *nwc = dynamic_cast<NWidgetPIPContainer *>(*dest);
-				if (nwc != nullptr) nwc->SetPIP(parts->u.pip.pre, parts->u.pip.inter, parts->u.pip.post);
+				if (nwc != nullptr) nwc->SetPIP(nwid_begin->u.pip.pre, nwid_begin->u.pip.inter, nwid_begin->u.pip.post);
 
 				NWidgetBackground *nwb = dynamic_cast<NWidgetBackground *>(*dest);
-				if (nwb != nullptr) nwb->SetPIP(parts->u.pip.pre, parts->u.pip.inter, parts->u.pip.post);
+				if (nwb != nullptr) nwb->SetPIP(nwid_begin->u.pip.pre, nwid_begin->u.pip.inter, nwid_begin->u.pip.post);
 				break;
 			}
 
 			case WPT_SCROLLBAR: {
 				NWidgetCore *nwc = dynamic_cast<NWidgetCore *>(*dest);
 				if (nwc != nullptr) {
-					nwc->scrollbar_index = parts->u.widget.index;
+					nwc->scrollbar_index = nwid_begin->u.widget.index;
 				}
 				break;
 			}
@@ -3162,15 +3162,15 @@ static int MakeNWidget(const NWidgetPart *parts, int count, NWidgetBase **dest,
 
 			case NWID_VIEWPORT:
 				if (*dest != nullptr) return num_used;
-				*dest = new NWidgetViewport(parts->u.widget.index);
-				*biggest_index = std::max(*biggest_index, (int)parts->u.widget.index);
+				*dest = new NWidgetViewport(nwid_begin->u.widget.index);
+				*biggest_index = std::max(*biggest_index, (int)nwid_begin->u.widget.index);
 				break;
 
 			case NWID_HSCROLLBAR:
 			case NWID_VSCROLLBAR:
 				if (*dest != nullptr) return num_used;
-				*dest = new NWidgetScrollbar(parts->type, parts->u.widget.colour, parts->u.widget.index);
-				*biggest_index = std::max(*biggest_index, (int)parts->u.widget.index);
+				*dest = new NWidgetScrollbar(nwid_begin->type, nwid_begin->u.widget.colour, nwid_begin->u.widget.index);
+				*biggest_index = std::max(*biggest_index, (int)nwid_begin->u.widget.index);
 				break;
 
 			case NWID_SELECTION: {
@@ -3178,20 +3178,20 @@ static int MakeNWidget(const NWidgetPart *parts, int count, NWidgetBase **dest,
 				NWidgetStacked *nws = new NWidgetStacked();
 				*dest = nws;
 				*fill_dest = true;
-				nws->SetIndex(parts->u.widget.index);
-				*biggest_index = std::max(*biggest_index, (int)parts->u.widget.index);
+				nws->SetIndex(nwid_begin->u.widget.index);
+				*biggest_index = std::max(*biggest_index, (int)nwid_begin->u.widget.index);
 				break;
 			}
 
 			default:
 				if (*dest != nullptr) return num_used;
-				assert((parts->type & WWT_MASK) < WWT_LAST || (parts->type & WWT_MASK) == NWID_BUTTON_DROPDOWN);
-				*dest = new NWidgetLeaf(parts->type, parts->u.widget.colour, parts->u.widget.index, 0x0, STR_NULL);
-				*biggest_index = std::max(*biggest_index, (int)parts->u.widget.index);
+				assert((nwid_begin->type & WWT_MASK) < WWT_LAST || (nwid_begin->type & WWT_MASK) == NWID_BUTTON_DROPDOWN);
+				*dest = new NWidgetLeaf(nwid_begin->type, nwid_begin->u.widget.colour, nwid_begin->u.widget.index, 0x0, STR_NULL);
+				*biggest_index = std::max(*biggest_index, (int)nwid_begin->u.widget.index);
 				break;
 		}
 		num_used++;
-		parts++;
+		nwid_begin++;
 	}
 
 	return num_used;
@@ -3199,14 +3199,14 @@ static int MakeNWidget(const NWidgetPart *parts, int count, NWidgetBase **dest,
 
 /**
  * Build a nested widget tree by recursively filling containers with nested widgets read from their parts.
- * @param parts  Array with parts of the nested widgets.
- * @param count  Length of the \a parts array.
+ * @param nwid_begin Pointer to beginning of nested widget parts.
+ * @param nwid_end Pointer to ending of nested widget parts.
  * @param parent Pointer or container to use for storing the child widgets (*parent == nullptr or *parent == container or background widget).
  * @param biggest_index Pointer to biggest nested widget index in the tree.
  * @return Number of widget part elements used to fill the container.
  * @post \c *biggest_index contains the largest widget index of the tree and \c -1 if no index is used.
  */
-static int MakeWidgetTree(const NWidgetPart *parts, int count, NWidgetBase **parent, int *biggest_index)
+static int MakeWidgetTree(const NWidgetPart *nwid_begin, const NWidgetPart *nwid_end, NWidgetBase **parent, int *biggest_index)
 {
 	/* If *parent == nullptr, only the first widget is read and returned. Otherwise, *parent must point to either
 	 * a #NWidgetContainer or a #NWidgetBackground object, and parts are added as much as possible. */
@@ -3218,8 +3218,8 @@ static int MakeWidgetTree(const NWidgetPart *parts, int count, NWidgetBase **par
 	for (;;) {
 		NWidgetBase *sub_widget = nullptr;
 		bool fill_sub = false;
-		int num_used = MakeNWidget(parts, count - total_used, &sub_widget, &fill_sub, biggest_index);
-		parts += num_used;
+		int num_used = MakeNWidget(nwid_begin, nwid_end, &sub_widget, &fill_sub, biggest_index);
+		nwid_begin += num_used;
 		total_used += num_used;
 
 		/* Break out of loop when end reached */
@@ -3230,8 +3230,8 @@ static int MakeWidgetTree(const NWidgetPart *parts, int count, NWidgetBase **par
 		if (fill_sub && (tp == NWID_HORIZONTAL || tp == NWID_HORIZONTAL_LTR || tp == NWID_VERTICAL || tp == NWID_MATRIX
 							|| tp == WWT_PANEL || tp == WWT_FRAME || tp == WWT_INSET || tp == NWID_SELECTION)) {
 			NWidgetBase *sub_ptr = sub_widget;
-			num_used = MakeWidgetTree(parts, count - total_used, &sub_ptr, biggest_index);
-			parts += num_used;
+			num_used = MakeWidgetTree(nwid_begin, nwid_end, &sub_ptr, biggest_index);
+			nwid_begin += num_used;
 			total_used += num_used;
 		}
 
@@ -3244,17 +3244,17 @@ static int MakeWidgetTree(const NWidgetPart *parts, int count, NWidgetBase **par
 		}
 	}
 
-	if (count == total_used) return total_used; // Reached the end of the array of parts?
+	if (nwid_begin == nwid_end) return total_used; // Reached the end of the array of parts?
 
-	assert(total_used < count);
-	assert(parts->type == WPT_ENDCONTAINER);
-	return total_used + 1; // *parts is also 'used'
+	assert(nwid_begin < nwid_end);
+	assert(nwid_begin->type == WPT_ENDCONTAINER);
+	return total_used + 1; // *nwid_begin is also 'used'
 }
 
 /**
  * Construct a nested widget tree from an array of parts.
- * @param parts Array with parts of the widgets.
- * @param count Length of the \a parts array.
+ * @param nwid_begin Pointer to beginning of nested widget parts.
+ * @param nwid_end Pointer to ending of nested widget parts.
  * @param biggest_index Pointer to biggest nested widget index collected in the tree.
  * @param container Container to add the nested widgets to. In case it is nullptr a vertical container is used.
  * @return Root of the nested widget tree, a vertical container containing the entire GUI.
@@ -3262,12 +3262,12 @@ static int MakeWidgetTree(const NWidgetPart *parts, int count, NWidgetBase **par
  * @pre \c biggest_index != nullptr
  * @post \c *biggest_index contains the largest widget index of the tree and \c -1 if no index is used.
  */
-NWidgetContainer *MakeNWidgets(const NWidgetPart *parts, int count, int *biggest_index, NWidgetContainer *container)
+NWidgetContainer *MakeNWidgets(const NWidgetPart *nwid_begin, const NWidgetPart *nwid_end, int *biggest_index, NWidgetContainer *container)
 {
 	*biggest_index = -1;
 	if (container == nullptr) container = new NWidgetVertical();
 	NWidgetBase *cont_ptr = container;
-	MakeWidgetTree(parts, count, &cont_ptr, biggest_index);
+	MakeWidgetTree(nwid_begin, nwid_end, &cont_ptr, biggest_index);
 	return container;
 }
 
@@ -3275,8 +3275,8 @@ NWidgetContainer *MakeNWidgets(const NWidgetPart *parts, int count, int *biggest
  * Make a nested widget tree for a window from a parts array. Besides loading, it inserts a shading selection widget
  * between the title bar and the window body if the first widget in the parts array looks like a title bar (it is a horizontal
  * container with a caption widget) and has a shade box widget.
- * @param parts Array with parts of the widgets.
- * @param count Length of the \a parts array.
+ * @param nwid_begin Pointer to beginning of nested widget parts.
+ * @param nwid_end Pointer to ending of nested widget parts.
  * @param biggest_index Pointer to biggest nested widget index collected in the tree.
  * @param[out] shade_select Pointer to the inserted shade selection widget (\c nullptr if not unserted).
  * @return Root of the nested widget tree, a vertical container containing the entire GUI.
@@ -3284,20 +3284,19 @@ NWidgetContainer *MakeNWidgets(const NWidgetPart *parts, int count, int *biggest
  * @pre \c biggest_index != nullptr
  * @post \c *biggest_index contains the largest widget index of the tree and \c -1 if no index is used.
  */
-NWidgetContainer *MakeWindowNWidgetTree(const NWidgetPart *parts, int count, int *biggest_index, NWidgetStacked **shade_select)
+NWidgetContainer *MakeWindowNWidgetTree(const NWidgetPart *nwid_begin, const NWidgetPart *nwid_end, int *biggest_index, NWidgetStacked **shade_select)
 {
 	*biggest_index = -1;
 
 	/* Read the first widget recursively from the array. */
 	NWidgetBase *nwid = nullptr;
-	int num_used = MakeWidgetTree(parts, count, &nwid, biggest_index);
+	int num_used = MakeWidgetTree(nwid_begin, nwid_end, &nwid, biggest_index);
 	assert(nwid != nullptr);
-	parts += num_used;
-	count -= num_used;
+	nwid_begin += num_used;
 
 	NWidgetContainer *root = new NWidgetVertical;
 	root->Add(nwid);
-	if (count == 0) { // There is no body at all.
+	if (nwid_begin == nwid_end) { // There is no body at all.
 		*shade_select = nullptr;
 		return root;
 	}
@@ -3318,7 +3317,7 @@ NWidgetContainer *MakeWindowNWidgetTree(const NWidgetPart *parts, int count, int
 
 	/* Load the remaining parts into 'body'. */
 	int biggest2 = -1;
-	MakeNWidgets(parts, count, &biggest2, body);
+	MakeNWidgets(nwid_begin, nwid_end, &biggest2, body);
 
 	*biggest_index = std::max(*biggest_index, biggest2);
 	return root;
diff --git a/src/widget_type.h b/src/widget_type.h
index 6edbdf0533..f00577e9c4 100644
--- a/src/widget_type.h
+++ b/src/widget_type.h
@@ -1296,8 +1296,8 @@ static inline NWidgetPart NWidgetFunction(NWidgetFunctionType *func_ptr)
 	return part;
 }
 
-NWidgetContainer *MakeNWidgets(const NWidgetPart *parts, int count, int *biggest_index, NWidgetContainer *container);
-NWidgetContainer *MakeWindowNWidgetTree(const NWidgetPart *parts, int count, int *biggest_index, NWidgetStacked **shade_select);
+NWidgetContainer *MakeNWidgets(const NWidgetPart *nwid_begin, const NWidgetPart *nwid_end, int *biggest_index, NWidgetContainer *container);
+NWidgetContainer *MakeWindowNWidgetTree(const NWidgetPart *nwid_begin, const NWidgetPart *nwid_end, int *biggest_index, NWidgetStacked **shade_select);
 
 NWidgetBase *MakeCompanyButtonRows(int *biggest_index, int widget_first, int widget_last, Colours button_colour, int max_length, StringID button_tooltip);
 
diff --git a/src/widgets/dropdown.cpp b/src/widgets/dropdown.cpp
index d43e3f995f..137c375dcb 100644
--- a/src/widgets/dropdown.cpp
+++ b/src/widgets/dropdown.cpp
@@ -104,7 +104,7 @@ static WindowDesc _dropdown_desc(
 	WDP_MANUAL, nullptr, 0, 0,
 	WC_DROPDOWN_MENU, WC_NONE,
 	WDF_NO_FOCUS,
-	_nested_dropdown_menu_widgets, lengthof(_nested_dropdown_menu_widgets)
+	std::begin(_nested_dropdown_menu_widgets), std::end(_nested_dropdown_menu_widgets)
 );
 
 /** Drop-down menu window */
diff --git a/src/window.cpp b/src/window.cpp
index ba8a06a1c8..839ccbb469 100644
--- a/src/window.cpp
+++ b/src/window.cpp
@@ -104,14 +104,14 @@ std::string _windows_file;
 /** Window description constructor. */
 WindowDesc::WindowDesc(WindowPosition def_pos, const char *ini_key, int16_t def_width_trad, int16_t def_height_trad,
 			WindowClass window_class, WindowClass parent_class, uint32_t flags,
-			const NWidgetPart *nwid_parts, int16_t nwid_length, HotkeyList *hotkeys) :
+			const NWidgetPart *nwid_begin, const NWidgetPart *nwid_end, HotkeyList *hotkeys) :
 	default_pos(def_pos),
 	cls(window_class),
 	parent_cls(parent_class),
 	ini_key(ini_key),
 	flags(flags),
-	nwid_parts(nwid_parts),
-	nwid_length(nwid_length),
+	nwid_begin(nwid_begin),
+	nwid_end(nwid_end),
 	hotkeys(hotkeys),
 	pref_sticky(false),
 	pref_width(0),
@@ -1798,7 +1798,7 @@ static Point LocalGetWindowPlacement(const WindowDesc *desc, int16_t sm_width, i
 void Window::CreateNestedTree(bool fill_nested)
 {
 	int biggest_index = -1;
-	this->nested_root = MakeWindowNWidgetTree(this->window_desc->nwid_parts, this->window_desc->nwid_length, &biggest_index, &this->shade_select);
+	this->nested_root = MakeWindowNWidgetTree(this->window_desc->nwid_begin, this->window_desc->nwid_end, &biggest_index, &this->shade_select);
 	this->nested_array_size = (uint)(biggest_index + 1);
 
 	if (fill_nested) {
diff --git a/src/window_gui.h b/src/window_gui.h
index 1d0d884c54..77f6d20429 100644
--- a/src/window_gui.h
+++ b/src/window_gui.h
@@ -97,7 +97,7 @@ struct WindowDesc : ZeroedMemoryAllocator {
 
 	WindowDesc(WindowPosition default_pos, const char *ini_key, int16_t def_width_trad, int16_t def_height_trad,
 			WindowClass window_class, WindowClass parent_class, uint32_t flags,
-			const NWidgetPart *nwid_parts, int16_t nwid_length, HotkeyList *hotkeys = nullptr);
+			const NWidgetPart *nwid_begin, const NWidgetPart *nwid_end, HotkeyList *hotkeys = nullptr);
 
 	~WindowDesc();
 
@@ -106,8 +106,8 @@ struct WindowDesc : ZeroedMemoryAllocator {
 	WindowClass parent_cls;        ///< Class of the parent window. @see WindowClass
 	const char *ini_key;           ///< Key to store window defaults in openttd.cfg. \c nullptr if nothing shall be stored.
 	uint32_t flags;                  ///< Flags. @see WindowDefaultFlag
-	const NWidgetPart *nwid_parts; ///< Nested widget parts describing the window.
-	int16_t nwid_length;             ///< Length of the #nwid_parts array.
+	const NWidgetPart *nwid_begin; ///< Beginning of nested widget parts describing the window.
+	const NWidgetPart *nwid_end; ///< Ending of nested widget parts describing the window.
 	HotkeyList *hotkeys;           ///< Hotkeys for the window.
 
 	bool pref_sticky;              ///< Preferred stickyness.