diff --git a/src/widgets/ai_widget.h b/src/widgets/ai_widget.h
index 964026ff79..23144e0103 100644
--- a/src/widgets/ai_widget.h
+++ b/src/widgets/ai_widget.h
@@ -13,7 +13,7 @@
 #include "../textfile_type.h"
 
 /** Widgets of the #AIConfigWindow class. */
-enum AIConfigWidgets {
+enum AIConfigWidgets : WidgetID {
 	WID_AIC_BACKGROUND,       ///< Window background.
 	WID_AIC_DECREASE_NUMBER,  ///< Decrease the number of AIs.
 	WID_AIC_INCREASE_NUMBER,  ///< Increase the number of AIs.
diff --git a/src/widgets/airport_widget.h b/src/widgets/airport_widget.h
index 514a44e88a..4e16f4596e 100644
--- a/src/widgets/airport_widget.h
+++ b/src/widgets/airport_widget.h
@@ -11,7 +11,7 @@
 #define WIDGETS_AIRPORT_WIDGET_H
 
 /** Widgets of the #BuildAirToolbarWindow class. */
-enum AirportToolbarWidgets {
+enum AirportToolbarWidgets : WidgetID {
 	WID_AT_AIRPORT,  ///< Build airport button.
 	WID_AT_DEMOLISH, ///< Demolish button.
 
@@ -19,7 +19,7 @@ enum AirportToolbarWidgets {
 };
 
 /** Widgets of the #BuildAirportWindow class. */
-enum AirportPickerWidgets {
+enum AirportPickerWidgets : WidgetID {
 	WID_AP_CLASS_DROPDOWN,  ///< Dropdown of airport classes.
 	WID_AP_AIRPORT_LIST,    ///< List of airports.
 	WID_AP_SCROLLBAR,       ///< Scrollbar of the list.
diff --git a/src/widgets/autoreplace_widget.h b/src/widgets/autoreplace_widget.h
index ab0b14aad2..c5d8c158aa 100644
--- a/src/widgets/autoreplace_widget.h
+++ b/src/widgets/autoreplace_widget.h
@@ -11,7 +11,7 @@
 #define WIDGETS_AUTOREPLACE_WIDGET_H
 
 /** Widgets of the #ReplaceVehicleWindow class. */
-enum ReplaceVehicleWidgets {
+enum ReplaceVehicleWidgets : WidgetID {
 	WID_RV_CAPTION,                  ///< Caption of the window.
 
 	/* Sort dropdown at the right. */
diff --git a/src/widgets/bootstrap_widget.h b/src/widgets/bootstrap_widget.h
index 16a36cc5b4..073e382907 100644
--- a/src/widgets/bootstrap_widget.h
+++ b/src/widgets/bootstrap_widget.h
@@ -11,19 +11,19 @@
 #define WIDGETS_BOOTSTRAP_WIDGET_H
 
 /** Widgets of the #BootstrapBackground class. */
-enum BootstrapBackgroundWidgets {
+enum BootstrapBackgroundWidgets : WidgetID {
 	WID_BB_BACKGROUND, ///< Background of the window.
 };
 
 /** Widgets of the #BootstrapErrmsgWindow class. */
-enum BootstrapErrorMessageWidgets {
+enum BootstrapErrorMessageWidgets : WidgetID {
 	WID_BEM_CAPTION, ///< Caption of the window.
 	WID_BEM_MESSAGE, ///< Error message.
 	WID_BEM_QUIT,    ///< Quit button.
 };
 
 /** Widgets of the #BootstrapContentDownloadStatusWindow class. */
-enum BootstrapAskForDownloadWidgets {
+enum BootstrapAskForDownloadWidgets : WidgetID {
 	WID_BAFD_QUESTION, ///< The question whether to download.
 	WID_BAFD_YES,      ///< An affirmative answer to the question.
 	WID_BAFD_NO,       ///< An negative answer to the question.
diff --git a/src/widgets/bridge_widget.h b/src/widgets/bridge_widget.h
index d9b6adedda..0d8f46362f 100644
--- a/src/widgets/bridge_widget.h
+++ b/src/widgets/bridge_widget.h
@@ -11,7 +11,7 @@
 #define WIDGETS_BRIDGE_WIDGET_H
 
 /** Widgets of the #BuildBridgeWindow class. */
-enum BuildBridgeSelectionWidgets {
+enum BuildBridgeSelectionWidgets : WidgetID {
 	WID_BBS_CAPTION,           ///< Caption of the window.
 	WID_BBS_DROPDOWN_ORDER,    ///< Direction of sort dropdown.
 	WID_BBS_DROPDOWN_CRITERIA, ///< Criteria of sort dropdown.
diff --git a/src/widgets/build_vehicle_widget.h b/src/widgets/build_vehicle_widget.h
index d0374a83d3..df541b8c0f 100644
--- a/src/widgets/build_vehicle_widget.h
+++ b/src/widgets/build_vehicle_widget.h
@@ -11,7 +11,7 @@
 #define WIDGETS_BUILD_VEHICLE_WIDGET_H
 
 /** Widgets of the #BuildVehicleWindow class. */
-enum BuildVehicleWidgets {
+enum BuildVehicleWidgets : WidgetID {
 	WID_BV_CAPTION,                   ///< Caption of window.
 	WID_BV_SORT_ASCENDING_DESCENDING, ///< Sort direction.
 	WID_BV_SORT_DROPDOWN,             ///< Criteria of sorting dropdown.
diff --git a/src/widgets/cheat_widget.h b/src/widgets/cheat_widget.h
index b8ee75f52b..204358e6a5 100644
--- a/src/widgets/cheat_widget.h
+++ b/src/widgets/cheat_widget.h
@@ -11,7 +11,7 @@
 #define WIDGETS_CHEAT_WIDGET_H
 
 /** Widgets of the #CheatWindow class. */
-enum CheatWidgets {
+enum CheatWidgets : WidgetID {
 	WID_C_NOTE,  ///< Note on top of panel for use of cheat.
 	WID_C_PANEL, ///< Panel where all cheats are shown in.
 };
diff --git a/src/widgets/company_widget.h b/src/widgets/company_widget.h
index a2e3cb685f..f53f83a494 100644
--- a/src/widgets/company_widget.h
+++ b/src/widgets/company_widget.h
@@ -11,7 +11,7 @@
 #define WIDGETS_COMPANY_WIDGET_H
 
 /** Widgets of the #CompanyWindow class. */
-enum CompanyWidgets {
+enum CompanyWidgets : WidgetID {
 	WID_C_CAPTION,                    ///< Caption of the window.
 
 	WID_C_FACE,                       ///< View of the face.
@@ -54,7 +54,7 @@ enum CompanyWidgets {
 };
 
 /** Widgets of the #CompanyFinancesWindow class. */
-enum CompanyFinancesWidgets {
+enum CompanyFinancesWidgets : WidgetID {
 	WID_CF_CAPTION,        ///< Caption of the window.
 	WID_CF_TOGGLE_SIZE,    ///< Toggle windows size.
 	WID_CF_SEL_PANEL,      ///< Select panel or nothing.
@@ -78,7 +78,7 @@ enum CompanyFinancesWidgets {
 
 
 /** Widgets of the #SelectCompanyLiveryWindow class. */
-enum SelectCompanyLiveryWidgets {
+enum SelectCompanyLiveryWidgets : WidgetID {
 	WID_SCL_CAPTION,          ///< Caption of window.
 	WID_SCL_CLASS_GENERAL,    ///< Class general.
 	WID_SCL_CLASS_RAIL,       ///< Class rail.
@@ -102,7 +102,7 @@ enum SelectCompanyLiveryWidgets {
  * Do not change the order of the widgets from WID_SCMF_HAS_MOUSTACHE_EARRING to WID_SCMF_GLASSES_R,
  * this order is needed for the WE_CLICK event of DrawFaceStringLabel().
  */
-enum SelectCompanyManagerFaceWidgets {
+enum SelectCompanyManagerFaceWidgets : WidgetID {
 	WID_SCMF_CAPTION,                    ///< Caption of window.
 	WID_SCMF_TOGGLE_LARGE_SMALL,         ///< Toggle for large or small.
 	WID_SCMF_SELECT_FACE,                ///< Select face.
@@ -170,7 +170,7 @@ enum SelectCompanyManagerFaceWidgets {
 };
 
 /** Widgets of the #CompanyInfrastructureWindow class. */
-enum CompanyInfrastructureWidgets {
+enum CompanyInfrastructureWidgets : WidgetID {
 	WID_CI_CAPTION,       ///< Caption of window.
 	WID_CI_RAIL_DESC,     ///< Description of rail.
 	WID_CI_RAIL_COUNT,    ///< Count of rail.
@@ -187,7 +187,7 @@ enum CompanyInfrastructureWidgets {
 };
 
 /** Widgets of the #BuyCompanyWindow class. */
-enum BuyCompanyWidgets {
+enum BuyCompanyWidgets : WidgetID {
 	WID_BC_CAPTION,  ///< Caption of window.
 	WID_BC_FACE,     ///< Face button.
 	WID_BC_QUESTION, ///< Question text.
diff --git a/src/widgets/console_widget.h b/src/widgets/console_widget.h
index 1bc1be1f67..8f90631824 100644
--- a/src/widgets/console_widget.h
+++ b/src/widgets/console_widget.h
@@ -11,7 +11,7 @@
 #define WIDGETS_CONSOLE_WIDGET_H
 
 /** Widgets of the #IConsoleWindow class. */
-enum ConsoleWidgets {
+enum ConsoleWidgets : WidgetID {
 	WID_C_BACKGROUND, ///< Background of the console.
 };
 
diff --git a/src/widgets/date_widget.h b/src/widgets/date_widget.h
index 3b397dae47..45bc4e9966 100644
--- a/src/widgets/date_widget.h
+++ b/src/widgets/date_widget.h
@@ -11,7 +11,7 @@
 #define WIDGETS_DATE_WIDGET_H
 
 /** Widgets of the #SetDateWindow class. */
-enum SetDateWidgets {
+enum SetDateWidgets : WidgetID {
 	WID_SD_DAY,      ///< Dropdown for the day.
 	WID_SD_MONTH,    ///< Dropdown for the month.
 	WID_SD_YEAR,     ///< Dropdown for the year.
diff --git a/src/widgets/depot_widget.h b/src/widgets/depot_widget.h
index c162cb8b7d..f94f1263d2 100644
--- a/src/widgets/depot_widget.h
+++ b/src/widgets/depot_widget.h
@@ -11,7 +11,7 @@
 #define WIDGETS_DEPOT_WIDGET_H
 
 /** Widgets of the #DepotWindow class. */
-enum DepotWidgets {
+enum DepotWidgets : WidgetID {
 	WID_D_CAPTION,         ///< Caption of window.
 	WID_D_SELL,            ///< Sell button.
 	WID_D_SHOW_SELL_CHAIN, ///< Show sell chain panel.
diff --git a/src/widgets/dock_widget.h b/src/widgets/dock_widget.h
index 139fcd55bc..0a1f480eb6 100644
--- a/src/widgets/dock_widget.h
+++ b/src/widgets/dock_widget.h
@@ -11,14 +11,14 @@
 #define WIDGETS_DOCK_WIDGET_H
 
 /** Widgets of the #BuildDocksDepotWindow class. */
-enum BuildDockDepotWidgets {
+enum BuildDockDepotWidgets : WidgetID {
 	WID_BDD_BACKGROUND, ///< Background of the window.
 	WID_BDD_X,          ///< X-direction button.
 	WID_BDD_Y,          ///< Y-direction button.
 };
 
 /** Widgets of the #BuildDocksToolbarWindow class. */
-enum DockToolbarWidgets {
+enum DockToolbarWidgets : WidgetID {
 	WID_DT_CANAL,          ///< Build canal button.
 	WID_DT_LOCK,           ///< Build lock button.
 	WID_DT_DEMOLISH,       ///< Demolish aka dynamite button.
diff --git a/src/widgets/dropdown_widget.h b/src/widgets/dropdown_widget.h
index 21223179e9..b9a5f3e17a 100644
--- a/src/widgets/dropdown_widget.h
+++ b/src/widgets/dropdown_widget.h
@@ -11,7 +11,7 @@
 #define WIDGETS_DROPDOWN_WIDGET_H
 
 /** Widgets of the #DropdownWindow class. */
-enum DropdownMenuWidgets {
+enum DropdownMenuWidgets : WidgetID {
 	WID_DM_ITEMS,        ///< Panel showing the dropdown items.
 	WID_DM_SHOW_SCROLL,  ///< Hide scrollbar if too few items.
 	WID_DM_SCROLL,       ///< Scrollbar.
diff --git a/src/widgets/engine_widget.h b/src/widgets/engine_widget.h
index 5d3468efc6..e66319ba05 100644
--- a/src/widgets/engine_widget.h
+++ b/src/widgets/engine_widget.h
@@ -11,7 +11,7 @@
 #define WIDGETS_ENGINE_WIDGET_H
 
 /** Widgets of the #EnginePreviewWindow class. */
-enum EnginePreviewWidgets {
+enum EnginePreviewWidgets : WidgetID {
 	WID_EP_QUESTION, ///< The container for the question.
 	WID_EP_NO,       ///< No button.
 	WID_EP_YES,      ///< Yes button.
diff --git a/src/widgets/error_widget.h b/src/widgets/error_widget.h
index 7a7fa4af38..40519644e7 100644
--- a/src/widgets/error_widget.h
+++ b/src/widgets/error_widget.h
@@ -11,7 +11,7 @@
 #define WIDGETS_ERROR_WIDGET_H
 
 /** Widgets of the #ErrmsgWindow class. */
-enum ErrorMessageWidgets {
+enum ErrorMessageWidgets : WidgetID {
 	WID_EM_CAPTION, ///< Caption of the window.
 	WID_EM_FACE,    ///< Error title.
 	WID_EM_MESSAGE, ///< Error message.
diff --git a/src/widgets/fios_widget.h b/src/widgets/fios_widget.h
index 86995588ed..0d8e723848 100644
--- a/src/widgets/fios_widget.h
+++ b/src/widgets/fios_widget.h
@@ -11,7 +11,7 @@
 #define WIDGETS_FIOS_WIDGET_H
 
 /** Widgets of the #SaveLoadWindow class. */
-enum SaveLoadWidgets {
+enum SaveLoadWidgets : WidgetID {
 	WID_SL_CAPTION,                 ///< Caption of the window.
 	WID_SL_SORT_BYNAME,             ///< Sort by name button.
 	WID_SL_SORT_BYDATE,             ///< Sort by date button.
diff --git a/src/widgets/framerate_widget.h b/src/widgets/framerate_widget.h
index 49ee2f9528..0192b540c6 100644
--- a/src/widgets/framerate_widget.h
+++ b/src/widgets/framerate_widget.h
@@ -11,7 +11,7 @@
 #define WIDGETS_FRAMERATE_WIDGET_H
 
 /** Widgets of the #FramerateWindow class. */
-enum FramerateWindowWidgets {
+enum FramerateWindowWidgets : WidgetID {
 	WID_FRW_CAPTION,
 	WID_FRW_RATE_GAMELOOP,
 	WID_FRW_RATE_DRAWING,
@@ -26,7 +26,7 @@ enum FramerateWindowWidgets {
 };
 
 /** Widgets of the #FrametimeGraphWindow class. */
-enum FrametimeGraphWindowWidgets {
+enum FrametimeGraphWindowWidgets : WidgetID {
 	WID_FGW_CAPTION,
 	WID_FGW_GRAPH,
 };
diff --git a/src/widgets/game_widget.h b/src/widgets/game_widget.h
index 3a2d2d7082..5b105d9934 100644
--- a/src/widgets/game_widget.h
+++ b/src/widgets/game_widget.h
@@ -13,7 +13,7 @@
 #include "../textfile_type.h"
 
 /** Widgets of the #GSConfigWindow class. */
-enum GSConfigWidgets {
+enum GSConfigWidgets : WidgetID {
 	WID_GSC_BACKGROUND,       ///< Window background.
 	WID_GSC_GSLIST,           ///< List with current selected Game Script.
 	WID_GSC_SETTINGS,         ///< Panel to draw the Game Script settings on
diff --git a/src/widgets/genworld_widget.h b/src/widgets/genworld_widget.h
index 34d2f149d8..8d852a117b 100644
--- a/src/widgets/genworld_widget.h
+++ b/src/widgets/genworld_widget.h
@@ -11,7 +11,7 @@
 #define WIDGETS_GENWORLD_WIDGET_H
 
 /** Widgets of the #GenerateLandscapeWindow class. */
-enum GenerateLandscapeWidgets {
+enum GenerateLandscapeWidgets : WidgetID {
 	WID_GL_TEMPERATE,                   ///< Button with icon "Temperate".
 	WID_GL_ARCTIC,                      ///< Button with icon "Arctic".
 	WID_GL_TROPICAL,                    ///< Button with icon "Tropical".
@@ -69,7 +69,7 @@ enum GenerateLandscapeWidgets {
 };
 
 /** Widgets of the #CreateScenarioWindow class. */
-enum CreateScenarioWidgets {
+enum CreateScenarioWidgets : WidgetID {
 	WID_CS_TEMPERATE,              ///< Select temperate landscape style.
 	WID_CS_ARCTIC,                 ///< Select arctic landscape style.
 	WID_CS_TROPICAL,               ///< Select tropical landscape style.
@@ -87,7 +87,7 @@ enum CreateScenarioWidgets {
 };
 
 /** Widgets of the #GenerateProgressWindow class. */
-enum GenerationProgressWidgets {
+enum GenerationProgressWidgets : WidgetID {
 	WID_GP_PROGRESS_BAR,  ///< Progress bar.
 	WID_GP_PROGRESS_TEXT, ///< Text with the progress bar.
 	WID_GP_ABORT,         ///< Abort button.
diff --git a/src/widgets/goal_widget.h b/src/widgets/goal_widget.h
index 303eaa69e9..c34749022a 100644
--- a/src/widgets/goal_widget.h
+++ b/src/widgets/goal_widget.h
@@ -12,7 +12,7 @@
 #define WIDGETS_GOAL_WIDGET_H
 
 /** Widgets of the #GoalListWindow class. */
-enum GoalListWidgets {
+enum GoalListWidgets : WidgetID {
 	WID_GOAL_CAPTION,         ///< Caption of the window.
 	WID_GOAL_SELECT_BUTTONS,  ///< Selection widget for the title bar button.
 	WID_GOAL_GLOBAL_BUTTON,   ///< Button to show global goals.
@@ -22,7 +22,7 @@ enum GoalListWidgets {
 };
 
 /** Widgets of the #GoalQuestionWindow class. */
-enum GoalQuestionWidgets {
+enum GoalQuestionWidgets : WidgetID {
 	WID_GQ_CAPTION,        ///< Caption of the window.
 	WID_GQ_QUESTION,       ///< Question text.
 	WID_GQ_BUTTONS,        ///< Buttons selection (between 1, 2 or 3).
diff --git a/src/widgets/graph_widget.h b/src/widgets/graph_widget.h
index 2548c990cd..3d155ec565 100644
--- a/src/widgets/graph_widget.h
+++ b/src/widgets/graph_widget.h
@@ -14,7 +14,7 @@
 #include "../company_type.h"
 
 /** Widgets of the #GraphLegendWindow class. */
-enum GraphLegendWidgets {
+enum GraphLegendWidgets : WidgetID {
 	WID_GL_BACKGROUND,    ///< Background of the window.
 
 	WID_GL_FIRST_COMPANY, ///< First company in the legend.
@@ -22,7 +22,7 @@ enum GraphLegendWidgets {
 };
 
 /** Widgets of the #OperatingProfitGraphWindow class, #IncomeGraphWindow class, #DeliveredCargoGraphWindow class, and #CompanyValueGraphWindow class. */
-enum CompanyValueWidgets {
+enum CompanyValueWidgets : WidgetID {
 	WID_CV_KEY_BUTTON, ///< Key button.
 	WID_CV_BACKGROUND, ///< Background of the window.
 	WID_CV_GRAPH,      ///< Graph itself.
@@ -30,7 +30,7 @@ enum CompanyValueWidgets {
 };
 
 /** Widget of the #PerformanceHistoryGraphWindow class. */
-enum PerformanceHistoryGraphWidgets {
+enum PerformanceHistoryGraphWidgets : WidgetID {
 	WID_PHG_KEY,                  ///< Key button.
 	WID_PHG_DETAILED_PERFORMANCE, ///< Detailed performance.
 	WID_PHG_BACKGROUND,           ///< Background of the window.
@@ -39,7 +39,7 @@ enum PerformanceHistoryGraphWidgets {
 };
 
 /** Widget of the #PaymentRatesGraphWindow class. */
-enum CargoPaymentRatesWidgets {
+enum CargoPaymentRatesWidgets : WidgetID {
 	WID_CPR_BACKGROUND,      ///< Background of the window.
 	WID_CPR_HEADER,          ///< Header.
 	WID_CPR_GRAPH,           ///< Graph itself.
@@ -52,7 +52,7 @@ enum CargoPaymentRatesWidgets {
 };
 
 /** Widget of the #PerformanceRatingDetailWindow class. */
-enum PerformanceRatingDetailsWidgets {
+enum PerformanceRatingDetailsWidgets : WidgetID {
 	WID_PRD_SCORE_FIRST, ///< First entry in the score list.
 	WID_PRD_SCORE_LAST = WID_PRD_SCORE_FIRST + (SCORE_END - SCORE_BEGIN) - 1, ///< Last entry in the score list.
 
diff --git a/src/widgets/group_widget.h b/src/widgets/group_widget.h
index e097b5314e..c140917899 100644
--- a/src/widgets/group_widget.h
+++ b/src/widgets/group_widget.h
@@ -11,7 +11,7 @@
 #define WIDGETS_GROUP_WIDGET_H
 
 /** Widgets of the #VehicleGroupWindow class. */
-enum GroupListWidgets {
+enum GroupListWidgets : WidgetID {
 	WID_GL_CAPTION,                  ///< Caption of the window.
 	WID_GL_GROUP_BY_ORDER,           ///< Group order.
 	WID_GL_GROUP_BY_DROPDOWN,        ///< Group by dropdown list.
diff --git a/src/widgets/help_widget.h b/src/widgets/help_widget.h
index 5b898fc01c..d6715d9632 100644
--- a/src/widgets/help_widget.h
+++ b/src/widgets/help_widget.h
@@ -11,7 +11,7 @@
 #define WIDGETS_HELP_WIDGET_H
 
 /** Widgets of the #HelpWindow class. */
-enum HelpWindowWidgets {
+enum HelpWindowWidgets : WidgetID {
 	WID_HW_README,
 	WID_HW_CHANGELOG,
 	WID_HW_KNOWN_BUGS,
diff --git a/src/widgets/highscore_widget.h b/src/widgets/highscore_widget.h
index 394b8c9bf7..3cf6fef968 100644
--- a/src/widgets/highscore_widget.h
+++ b/src/widgets/highscore_widget.h
@@ -11,7 +11,7 @@
 #define WIDGETS_HIGHSCORE_WIDGET_H
 
 /** Widgets of the #EndGameHighScoreBaseWindow class and #HighScoreWindow class. */
-enum HighscoreWidgets {
+enum HighscoreWidgets : WidgetID {
 	WID_H_BACKGROUND, ///< Background of the window.
 };
 
diff --git a/src/widgets/industry_widget.h b/src/widgets/industry_widget.h
index ee74d90d54..da8de1c58f 100644
--- a/src/widgets/industry_widget.h
+++ b/src/widgets/industry_widget.h
@@ -11,7 +11,7 @@
 #define WIDGETS_INDUSTRY_WIDGET_H
 
 /** Widgets of the #BuildIndustryWindow class. */
-enum DynamicPlaceIndustriesWidgets {
+enum DynamicPlaceIndustriesWidgets : WidgetID {
 	WID_DPI_SCENARIO_EDITOR_PANE,            ///< Pane containing SE-only widgets.
 	WID_DPI_REMOVE_ALL_INDUSTRIES_WIDGET,    ///< Remove all industries button.
 	WID_DPI_CREATE_RANDOM_INDUSTRIES_WIDGET, ///< Create random industries button.
@@ -23,7 +23,7 @@ enum DynamicPlaceIndustriesWidgets {
 };
 
 /** Widgets of the #IndustryViewWindow class. */
-enum IndustryViewWidgets {
+enum IndustryViewWidgets : WidgetID {
 	WID_IV_CAPTION,  ///< Caption of the window.
 	WID_IV_VIEWPORT, ///< Viewport of the industry.
 	WID_IV_INFO,     ///< Info of the industry.
@@ -32,7 +32,7 @@ enum IndustryViewWidgets {
 };
 
 /** Widgets of the #IndustryDirectoryWindow class. */
-enum IndustryDirectoryWidgets {
+enum IndustryDirectoryWidgets : WidgetID {
 	WID_ID_DROPDOWN_ORDER,       ///< Dropdown for the order of the sort.
 	WID_ID_DROPDOWN_CRITERIA,    ///< Dropdown for the criteria of the sort.
 	WID_ID_FILTER_BY_ACC_CARGO,  ///< Accepted cargo filter dropdown list.
@@ -44,7 +44,7 @@ enum IndustryDirectoryWidgets {
 };
 
 /** Widgets of the #IndustryCargoesWindow class */
-enum IndustryCargoesWidgets {
+enum IndustryCargoesWidgets : WidgetID {
 	WID_IC_CAPTION,        ///< Caption of the window.
 	WID_IC_NOTIFY,         ///< Row of buttons at the bottom.
 	WID_IC_PANEL,          ///< Panel that shows the chain.
diff --git a/src/widgets/intro_widget.h b/src/widgets/intro_widget.h
index 6e5e70eea9..dcefc172be 100644
--- a/src/widgets/intro_widget.h
+++ b/src/widgets/intro_widget.h
@@ -11,7 +11,7 @@
 #define WIDGETS_INTRO_WIDGET_H
 
 /** Widgets of the #SelectGameWindow class. */
-enum SelectGameIntroWidgets {
+enum SelectGameIntroWidgets : WidgetID {
 	WID_SGI_GENERATE_GAME,         ///< Generate game button.
 	WID_SGI_LOAD_GAME,             ///< Load game button.
 	WID_SGI_PLAY_SCENARIO,         ///< Play scenario button.
diff --git a/src/widgets/league_widget.h b/src/widgets/league_widget.h
index 381d379a7e..d6f7c13717 100644
--- a/src/widgets/league_widget.h
+++ b/src/widgets/league_widget.h
@@ -11,12 +11,12 @@
 #define WIDGETS_LEAGUE_WIDGET_H
 
 /** Widget of the #PerformanceLeagueWindow class. */
-enum PerformanceLeagueWidgets {
+enum PerformanceLeagueWidgets : WidgetID {
 	WID_PLT_BACKGROUND, ///< Background of the window.
 };
 
 /** Widget of the #ScriptLeagueWindow class. */
-enum ScriptLeagueWidgets {
+enum ScriptLeagueWidgets : WidgetID {
 	WID_SLT_CAPTION,    ///< Caption of the window.
 	WID_SLT_BACKGROUND, ///< Background of the window.
 };
diff --git a/src/widgets/link_graph_legend_widget.h b/src/widgets/link_graph_legend_widget.h
index a0ff68ab07..a8b2357d72 100644
--- a/src/widgets/link_graph_legend_widget.h
+++ b/src/widgets/link_graph_legend_widget.h
@@ -14,7 +14,7 @@
 
 /** Widgets of the WC_LINKGRAPH_LEGEND. */
 
-enum LinkGraphLegendWidgets {
+enum LinkGraphLegendWidgets : WidgetID {
 	WID_LGL_CAPTION,           ///< Caption widget.
 	WID_LGL_SATURATION,        ///< Saturation legend.
 	WID_LGL_SATURATION_FIRST,
diff --git a/src/widgets/main_widget.h b/src/widgets/main_widget.h
index 51627da5c0..8c12f42620 100644
--- a/src/widgets/main_widget.h
+++ b/src/widgets/main_widget.h
@@ -11,7 +11,7 @@
 #define WIDGETS_MAIN_WIDGET_H
 
 /** Widgets of the #MainWindow class. */
-enum MainWidgets {
+enum MainWidgets : WidgetID {
 	WID_M_VIEWPORT, ///< Main window viewport.
 };
 
diff --git a/src/widgets/misc_widget.h b/src/widgets/misc_widget.h
index 61e916d1da..a3ec814f1b 100644
--- a/src/widgets/misc_widget.h
+++ b/src/widgets/misc_widget.h
@@ -11,25 +11,25 @@
 #define WIDGETS_MISC_WIDGET_H
 
 /** Widgets of the #LandInfoWindow class. */
-enum LandInfoWidgets {
+enum LandInfoWidgets : WidgetID {
 	WID_LI_LOCATION, ///< Scroll to location.
 	WID_LI_BACKGROUND, ///< Background of the window.
 };
 
 /** Widgets of the #TooltipsWindow class. */
-enum ToolTipsWidgets {
+enum ToolTipsWidgets : WidgetID {
 	WID_TT_BACKGROUND, ///< Background of the window.
 };
 
 /** Widgets of the #AboutWindow class. */
-enum AboutWidgets {
+enum AboutWidgets : WidgetID {
 	WID_A_SCROLLING_TEXT, ///< The actually scrolling text.
 	WID_A_WEBSITE,        ///< URL of OpenTTD website.
 	WID_A_COPYRIGHT,      ///< Copyright string
 };
 
 /** Widgets of the #QueryStringWindow class. */
-enum QueryStringWidgets {
+enum QueryStringWidgets : WidgetID {
 	WID_QS_CAPTION, ///< Caption of the window.
 	WID_QS_TEXT,    ///< Text of the query.
 	WID_QS_WARNING, ///< Warning label about password security
@@ -39,7 +39,7 @@ enum QueryStringWidgets {
 };
 
 /** Widgets of the #QueryWindow class. */
-enum QueryWidgets {
+enum QueryWidgets : WidgetID {
 	WID_Q_CAPTION, ///< Caption of the window.
 	WID_Q_TEXT,    ///< Text of the query.
 	WID_Q_NO,      ///< Yes button.
@@ -47,7 +47,7 @@ enum QueryWidgets {
 };
 
 /** Widgets of the #TextfileWindow class. */
-enum TextfileWidgets {
+enum TextfileWidgets : WidgetID {
 	WID_TF_CAPTION,      ///< The caption of the window.
 	WID_TF_NAVBACK,      ///< Navigate back button.
 	WID_TF_NAVFORWARD,   ///< Navigate forward button.
diff --git a/src/widgets/music_widget.h b/src/widgets/music_widget.h
index dc2e685325..bbb0a3e4d0 100644
--- a/src/widgets/music_widget.h
+++ b/src/widgets/music_widget.h
@@ -11,7 +11,7 @@
 #define WIDGETS_MUSIC_WIDGET_H
 
 /** Widgets of the #MusicTrackSelectionWindow class. */
-enum MusicTrackSelectionWidgets {
+enum MusicTrackSelectionWidgets : WidgetID {
 	WID_MTS_CAPTION,    ///< Window caption.
 	WID_MTS_LIST_LEFT,  ///< Left button.
 	WID_MTS_PLAYLIST,   ///< Playlist.
@@ -27,7 +27,7 @@ enum MusicTrackSelectionWidgets {
 };
 
 /** Widgets of the #MusicWindow class. */
-enum MusicWidgets {
+enum MusicWidgets : WidgetID {
 	WID_M_PREV,        ///< Previous button.
 	WID_M_NEXT,        ///< Next button.
 	WID_M_STOP,        ///< Stop button.
diff --git a/src/widgets/network_chat_widget.h b/src/widgets/network_chat_widget.h
index ccfb467f71..26a3a1e436 100644
--- a/src/widgets/network_chat_widget.h
+++ b/src/widgets/network_chat_widget.h
@@ -11,7 +11,7 @@
 #define WIDGETS_NETWORK_CHAT_WIDGET_H
 
 /** Widgets of the #NetworkChatWindow class. */
-enum NetWorkChatWidgets {
+enum NetWorkChatWidgets : WidgetID {
 	WID_NC_CLOSE,       ///< Close button.
 	WID_NC_BACKGROUND,  ///< Background of the window.
 	WID_NC_DESTINATION, ///< Destination.
diff --git a/src/widgets/network_content_widget.h b/src/widgets/network_content_widget.h
index c8092aefa8..38158272ba 100644
--- a/src/widgets/network_content_widget.h
+++ b/src/widgets/network_content_widget.h
@@ -13,14 +13,14 @@
 #include "../textfile_type.h"
 
 /** Widgets of the #NetworkContentDownloadStatusWindow class. */
-enum NetworkContentDownloadStatusWidgets {
+enum NetworkContentDownloadStatusWidgets : WidgetID {
 	WID_NCDS_PROGRESS_BAR,  ///< Simple progress bar.
 	WID_NCDS_PROGRESS_TEXT, ///< Text explaining what is happening.
 	WID_NCDS_CANCELOK,      ///< (Optional) Cancel/OK button.
 };
 
 /** Widgets of the #NetworkContentListWindow class. */
-enum NetworkContentListWidgets {
+enum NetworkContentListWidgets : WidgetID {
 	WID_NCL_BACKGROUND,     ///< Resize button.
 
 	WID_NCL_FILTER_CAPT,    ///< Caption for the filter editbox.
diff --git a/src/widgets/network_widget.h b/src/widgets/network_widget.h
index 087436a516..276874f92e 100644
--- a/src/widgets/network_widget.h
+++ b/src/widgets/network_widget.h
@@ -11,7 +11,7 @@
 #define WIDGETS_NETWORK_WIDGET_H
 
 /** Widgets of the #NetworkGameWindow class. */
-enum NetworkGameWidgets {
+enum NetworkGameWidgets : WidgetID {
 	WID_NG_MAIN,               ///< Main panel.
 
 	WID_NG_CLIENT_LABEL,       ///< Label in front of client name edit box.
@@ -49,7 +49,7 @@ enum NetworkGameWidgets {
 };
 
 /** Widgets of the #NetworkStartServerWindow class. */
-enum NetworkStartServerWidgets {
+enum NetworkStartServerWidgets : WidgetID {
 	WID_NSS_BACKGROUND,        ///< Background of the window.
 	WID_NSS_GAMENAME_LABEL,    ///< Label for the game name.
 	WID_NSS_GAMENAME,          ///< Background for editbox to set game name.
@@ -74,7 +74,7 @@ enum NetworkStartServerWidgets {
 };
 
 /** Widgets of the #NetworkClientListWindow class. */
-enum ClientListWidgets {
+enum ClientListWidgets : WidgetID {
 	WID_CL_PANEL,                      ///< Panel of the window.
 	WID_CL_SERVER_SELECTOR,            ///< Selector to hide the server frame.
 	WID_CL_SERVER_NAME,                ///< Server name.
@@ -91,14 +91,14 @@ enum ClientListWidgets {
 };
 
 /** Widgets of the #NetworkJoinStatusWindow class. */
-enum NetworkJoinStatusWidgets {
+enum NetworkJoinStatusWidgets : WidgetID {
 	WID_NJS_PROGRESS_BAR,  ///< Simple progress bar.
 	WID_NJS_PROGRESS_TEXT, ///< Text explaining what is happening.
 	WID_NJS_CANCELOK,      ///< Cancel / OK button.
 };
 
 /** Widgets of the #NetworkCompanyPasswordWindow class. */
-enum NetworkCompanyPasswordWidgets {
+enum NetworkCompanyPasswordWidgets : WidgetID {
 	WID_NCP_BACKGROUND,               ///< Background of the window.
 	WID_NCP_LABEL,                    ///< Label in front of the password field.
 	WID_NCP_PASSWORD,                 ///< Input field for the password.
@@ -109,7 +109,7 @@ enum NetworkCompanyPasswordWidgets {
 };
 
 /** Widgets of the #NetworkAskRelayWindow class. */
-enum NetworkAskRelayWidgets {
+enum NetworkAskRelayWidgets : WidgetID {
 	WID_NAR_CAPTION,    ///< Caption of the window.
 	WID_NAR_TEXT,       ///< Text in the window.
 	WID_NAR_NO,         ///< "No" button.
@@ -118,7 +118,7 @@ enum NetworkAskRelayWidgets {
 };
 
 /** Widgets of the #NetworkAskSurveyWindow class. */
-enum NetworkAskSurveyWidgets {
+enum NetworkAskSurveyWidgets : WidgetID {
 	WID_NAS_CAPTION,    ///< Caption of the window.
 	WID_NAS_TEXT,       ///< Text in the window.
 	WID_NAS_PREVIEW,    ///< "Preview" button.
diff --git a/src/widgets/newgrf_debug_widget.h b/src/widgets/newgrf_debug_widget.h
index 910d212199..b4dffcaad2 100644
--- a/src/widgets/newgrf_debug_widget.h
+++ b/src/widgets/newgrf_debug_widget.h
@@ -11,7 +11,7 @@
 #define WIDGETS_NEWGRF_DEBUG_WIDGET_H
 
 /** Widgets of the #NewGRFInspectWindow class. */
-enum NewGRFInspectWidgets {
+enum NewGRFInspectWidgets : WidgetID {
 	WID_NGRFI_CAPTION,   ///< The caption bar of course.
 	WID_NGRFI_PARENT,    ///< Inspect the parent.
 	WID_NGRFI_VEH_PREV,  ///< Go to previous vehicle in chain.
@@ -22,7 +22,7 @@ enum NewGRFInspectWidgets {
 };
 
 /** Widgets of the #SpriteAlignerWindow class. */
-enum SpriteAlignerWidgets {
+enum SpriteAlignerWidgets : WidgetID {
 	WID_SA_CAPTION,     ///< Caption of the window.
 	WID_SA_PREVIOUS,    ///< Skip to the previous sprite.
 	WID_SA_GOTO,        ///< Go to a given sprite.
diff --git a/src/widgets/newgrf_widget.h b/src/widgets/newgrf_widget.h
index da4e4d584d..d4bab8e200 100644
--- a/src/widgets/newgrf_widget.h
+++ b/src/widgets/newgrf_widget.h
@@ -14,7 +14,7 @@
 #include "../textfile_type.h"
 
 /** Widgets of the #NewGRFParametersWindow class. */
-enum NewGRFParametersWidgets {
+enum NewGRFParametersWidgets : WidgetID {
 	WID_NP_CAPTION,          ///< Caption of the window.
 	WID_NP_SHOW_NUMPAR,      ///< #NWID_SELECTION to optionally display #WID_NP_NUMPAR.
 	WID_NP_NUMPAR_DEC,       ///< Button to decrease number of parameters.
@@ -32,7 +32,7 @@ enum NewGRFParametersWidgets {
 };
 
 /** Widgets of the #NewGRFWindow class. */
-enum NewGRFStateWidgets {
+enum NewGRFStateWidgets : WidgetID {
 	WID_NS_PRESET_LIST,       ///< Active NewGRF preset.
 	WID_NS_PRESET_SAVE,       ///< Save list of active NewGRFs as presets.
 	WID_NS_PRESET_DELETE,     ///< Delete active preset.
@@ -63,7 +63,7 @@ enum NewGRFStateWidgets {
 };
 
 /** Widgets of the #SavePresetWindow class. */
-enum SavePresetWidgets {
+enum SavePresetWidgets : WidgetID {
 	WID_SVP_PRESET_LIST, ///< List with available preset names.
 	WID_SVP_SCROLLBAR,   ///< Scrollbar for the list available preset names.
 	WID_SVP_EDITBOX,     ///< Edit box for changing the preset name.
@@ -72,7 +72,7 @@ enum SavePresetWidgets {
 };
 
 /** Widgets of the #ScanProgressWindow class. */
-enum ScanProgressWidgets {
+enum ScanProgressWidgets : WidgetID {
 	WID_SP_PROGRESS_BAR,  ///< Simple progress bar.
 	WID_SP_PROGRESS_TEXT, ///< Text explaining what is happening.
 };
diff --git a/src/widgets/news_widget.h b/src/widgets/news_widget.h
index e5b8934439..68d59fa133 100644
--- a/src/widgets/news_widget.h
+++ b/src/widgets/news_widget.h
@@ -13,7 +13,7 @@
 #include "../news_type.h"
 
 /** Widgets of the #NewsWindow class. */
-enum NewsWidgets {
+enum NewsWidgets : WidgetID {
 	WID_N_PANEL,       ///< Panel of the window.
 	WID_N_TITLE,       ///< Title of the company news.
 	WID_N_HEADLINE,    ///< The news headline.
@@ -35,7 +35,7 @@ enum NewsWidgets {
 };
 
 /** Widgets of the #MessageHistoryWindow class. */
-enum MessageHistoryWidgets {
+enum MessageHistoryWidgets : WidgetID {
 	WID_MH_STICKYBOX,  ///< Stickybox.
 	WID_MH_BACKGROUND, ///< Background of the window.
 	WID_MH_SCROLLBAR,  ///< Scrollbar for the list.
diff --git a/src/widgets/object_widget.h b/src/widgets/object_widget.h
index 9afb783c56..9adf13dde7 100644
--- a/src/widgets/object_widget.h
+++ b/src/widgets/object_widget.h
@@ -11,7 +11,7 @@
 #define WIDGETS_OBJECT_WIDGET_H
 
 /** Widgets of the #BuildObjectWindow class. */
-enum BuildObjectWidgets {
+enum BuildObjectWidgets : WidgetID {
 	WID_BO_FILTER,         ///< The filter text box for the object list.
 	WID_BO_CLASS_LIST,     ///< The list with classes.
 	WID_BO_SCROLLBAR,      ///< The scrollbar associated with the list.
diff --git a/src/widgets/order_widget.h b/src/widgets/order_widget.h
index 82ca472e20..3177359de9 100644
--- a/src/widgets/order_widget.h
+++ b/src/widgets/order_widget.h
@@ -11,7 +11,7 @@
 #define WIDGETS_ORDER_WIDGET_H
 
 /** Widgets of the #OrdersWindow class. */
-enum OrderWidgets {
+enum OrderWidgets : WidgetID {
 	WID_O_CAPTION,                   ///< Caption of the window.
 	WID_O_TIMETABLE_VIEW,            ///< Toggle timetable view.
 	WID_O_ORDER_LIST,                ///< Order list panel.
diff --git a/src/widgets/osk_widget.h b/src/widgets/osk_widget.h
index ccda502fff..ae84037b53 100644
--- a/src/widgets/osk_widget.h
+++ b/src/widgets/osk_widget.h
@@ -11,7 +11,7 @@
 #define WIDGETS_OSK_WIDGET_H
 
 /** Widgets of the #OskWindow class. */
-enum OnScreenKeyboardWidgets {
+enum OnScreenKeyboardWidgets : WidgetID {
 	WID_OSK_CAPTION,   ///< Caption of window.
 	WID_OSK_TEXT,      ///< Edit box.
 	WID_OSK_CANCEL,    ///< Cancel key.
diff --git a/src/widgets/rail_widget.h b/src/widgets/rail_widget.h
index 479915cc01..b418e45bd1 100644
--- a/src/widgets/rail_widget.h
+++ b/src/widgets/rail_widget.h
@@ -11,7 +11,7 @@
 #define WIDGETS_RAIL_WIDGET_H
 
 /** Widgets of the #BuildRailToolbarWindow class. */
-enum RailToolbarWidgets {
+enum RailToolbarWidgets : WidgetID {
 	/* Name starts with RA instead of R, because of collision with RoadToolbarWidgets */
 	WID_RAT_CAPTION,        ///< Caption of the window.
 	WID_RAT_BUILD_NS,       ///< Build rail along the game view Y axis.
@@ -33,7 +33,7 @@ enum RailToolbarWidgets {
 };
 
 /** Widgets of the #BuildRailStationWindow class. */
-enum BuildRailStationWidgets {
+enum BuildRailStationWidgets : WidgetID {
 	/* Name starts with BRA instead of BR, because of collision with BuildRoadStationWidgets */
 	WID_BRAS_PLATFORM_DIR_X,       ///< Button to select '/' view.
 	WID_BRAS_PLATFORM_DIR_Y,       ///< Button to select '\' view.
@@ -79,7 +79,7 @@ enum BuildRailStationWidgets {
 };
 
 /** Widgets of the #BuildSignalWindow class. */
-enum BuildSignalWidgets {
+enum BuildSignalWidgets : WidgetID {
 	WID_BS_CAPTION,            ///< Caption for the Signal Selection window.
 	WID_BS_TOGGLE_SIZE,        ///< Toggle showing advanced signal types.
 	WID_BS_SEMAPHORE_NORM,     ///< Build a semaphore normal block signal.
@@ -109,7 +109,7 @@ enum BuildSignalWidgets {
 };
 
 /** Widgets of the #BuildRailDepotWindow class. */
-enum BuildRailDepotWidgets {
+enum BuildRailDepotWidgets : WidgetID {
 	/* Name starts with BRA instead of BR, because of collision with BuildRoadDepotWidgets */
 	WID_BRAD_DEPOT_NE, ///< Build a depot with the entrance in the north east.
 	WID_BRAD_DEPOT_SE, ///< Build a depot with the entrance in the south east.
@@ -118,7 +118,7 @@ enum BuildRailDepotWidgets {
 };
 
 /** Widgets of the #BuildRailWaypointWindow class. */
-enum BuildRailWaypointWidgets {
+enum BuildRailWaypointWidgets : WidgetID {
 	WID_BRW_FILTER,          ///< Text filter.
 	WID_BRW_WAYPOINT_MATRIX, ///< Matrix with waypoints.
 	WID_BRW_WAYPOINT,        ///< A single waypoint.
diff --git a/src/widgets/road_widget.h b/src/widgets/road_widget.h
index 9050480bfb..416e1868c7 100644
--- a/src/widgets/road_widget.h
+++ b/src/widgets/road_widget.h
@@ -11,7 +11,7 @@
 #define WIDGETS_ROAD_WIDGET_H
 
 /** Widgets of the #BuildRoadToolbarWindow class. */
-enum RoadToolbarWidgets {
+enum RoadToolbarWidgets : WidgetID {
 	/* Name starts with RO instead of R, because of collision with RailToolbarWidgets */
 	WID_ROT_CAPTION,        ///< Caption of the window
 	WID_ROT_ROAD_X,         ///< Build road in x-direction.
@@ -31,7 +31,7 @@ enum RoadToolbarWidgets {
 };
 
 /** Widgets of the #BuildRoadDepotWindow class. */
-enum BuildRoadDepotWidgets {
+enum BuildRoadDepotWidgets : WidgetID {
 	/* Name starts with BRO instead of BR, because of collision with BuildRailDepotWidgets */
 	WID_BROD_CAPTION,   ///< Caption of the window.
 	WID_BROD_DEPOT_NE,  ///< Depot with NE entry.
@@ -41,7 +41,7 @@ enum BuildRoadDepotWidgets {
 };
 
 /** Widgets of the #BuildRoadStationWindow class. */
-enum BuildRoadStationWidgets {
+enum BuildRoadStationWidgets : WidgetID {
 	/* Name starts with BRO instead of BR, because of collision with BuildRailStationWidgets */
 	WID_BROS_CAPTION,                ///< Caption of the window.
 	WID_BROS_STATION_NE,             ///< Terminal station with NE entry.
diff --git a/src/widgets/screenshot_widget.h b/src/widgets/screenshot_widget.h
index 6f42b784d6..7fc3a0779f 100644
--- a/src/widgets/screenshot_widget.h
+++ b/src/widgets/screenshot_widget.h
@@ -12,7 +12,7 @@
 
 /** Widgets of the #ScreenshotWindow class. */
 
-enum ScreenshotWindowWidgets {
+enum ScreenshotWindowWidgets : WidgetID {
 	WID_SC_TAKE,             ///< Button for taking a normal screenshot
 	WID_SC_TAKE_ZOOMIN,      ///< Button for taking a zoomed in screenshot
 	WID_SC_TAKE_DEFAULTZOOM, ///< Button for taking a screenshot at normal zoom
diff --git a/src/widgets/script_widget.h b/src/widgets/script_widget.h
index d4ba17e452..253e1673ed 100644
--- a/src/widgets/script_widget.h
+++ b/src/widgets/script_widget.h
@@ -13,7 +13,7 @@
 #include "../company_type.h"
 
 /** Widgets of the #ScriptListWindow class. */
-enum ScriptListWidgets {
+enum ScriptListWidgets : WidgetID {
 	WID_SCRL_CAPTION,   ///< Caption of the window.
 	WID_SCRL_LIST,      ///< The matrix with all available Scripts.
 	WID_SCRL_SCROLLBAR, ///< Scrollbar next to the Script list.
@@ -23,7 +23,7 @@ enum ScriptListWidgets {
 };
 
 /** Widgets of the #ScriptSettingsWindow class. */
-enum ScriptSettingsWidgets {
+enum ScriptSettingsWidgets : WidgetID {
 	WID_SCRS_CAPTION,    ///< Caption of the window.
 	WID_SCRS_BACKGROUND, ///< Panel to draw the settings on.
 	WID_SCRS_SCROLLBAR,  ///< Scrollbar to scroll through all settings.
@@ -34,7 +34,7 @@ enum ScriptSettingsWidgets {
 };
 
 /** Widgets of the #ScriptDebugWindow class. */
-enum ScriptDebugWidgets {
+enum ScriptDebugWidgets : WidgetID {
 	WID_SCRD_VIEW,                 ///< The row of company buttons.
 	WID_SCRD_NAME_TEXT,            ///< Name of the current selected.
 	WID_SCRD_SETTINGS,             ///< Settings button.
diff --git a/src/widgets/settings_widget.h b/src/widgets/settings_widget.h
index 33b02f3d88..b59778a14d 100644
--- a/src/widgets/settings_widget.h
+++ b/src/widgets/settings_widget.h
@@ -11,7 +11,7 @@
 #define WIDGETS_SETTINGS_WIDGET_H
 
 /** Widgets of the #GameOptionsWindow class. */
-enum GameOptionsWidgets {
+enum GameOptionsWidgets : WidgetID {
 	WID_GO_TAB_GENERAL,            ///< General tab.
 	WID_GO_TAB_GRAPHICS,           ///< Graphics tab.
 	WID_GO_TAB_SOUND,              ///< Sound tab.
@@ -54,7 +54,7 @@ enum GameOptionsWidgets {
 };
 
 /** Widgets of the #GameSettingsWindow class. */
-enum GameSettingsWidgets {
+enum GameSettingsWidgets : WidgetID {
 	WID_GS_FILTER,             ///< Text filter.
 	WID_GS_OPTIONSPANEL,       ///< Panel widget containing the option lists.
 	WID_GS_SCROLLBAR,          ///< Scrollbar.
@@ -71,7 +71,7 @@ enum GameSettingsWidgets {
 };
 
 /** Widgets of the #CustomCurrencyWindow class. */
-enum CustomCurrencyWidgets {
+enum CustomCurrencyWidgets : WidgetID {
 	WID_CC_RATE_DOWN,      ///< Down button.
 	WID_CC_RATE_UP,        ///< Up button.
 	WID_CC_RATE,           ///< Rate of currency.
diff --git a/src/widgets/sign_widget.h b/src/widgets/sign_widget.h
index 1a05dd349b..0ab5fe060d 100644
--- a/src/widgets/sign_widget.h
+++ b/src/widgets/sign_widget.h
@@ -11,7 +11,7 @@
 #define WIDGETS_SIGN_WIDGET_H
 
 /** Widgets of the #SignListWindow class. */
-enum SignListWidgets {
+enum SignListWidgets : WidgetID {
 	/* Name starts with SI instead of S, because of collision with SaveLoadWidgets */
 	WID_SIL_CAPTION,               ///< Caption of the window.
 	WID_SIL_LIST,                  ///< List of signs.
@@ -22,7 +22,7 @@ enum SignListWidgets {
 };
 
 /** Widgets of the #SignWindow class. */
-enum QueryEditSignWidgets {
+enum QueryEditSignWidgets : WidgetID {
 	WID_QES_CAPTION,  ///< Caption of the window.
 	WID_QES_LOCATION, ///< Scroll to sign location.
 	WID_QES_TEXT,     ///< Text of the query.
diff --git a/src/widgets/smallmap_widget.h b/src/widgets/smallmap_widget.h
index 79769a21cc..73c89df3d6 100644
--- a/src/widgets/smallmap_widget.h
+++ b/src/widgets/smallmap_widget.h
@@ -11,7 +11,7 @@
 #define WIDGETS_SMALLMAP_WIDGET_H
 
 /** Widgets of the #SmallMapWindow class. */
-enum SmallMapWidgets {
+enum SmallMapWidgets : WidgetID {
 	WID_SM_CAPTION,        ///< Caption of the window.
 	WID_SM_MAP_BORDER,     ///< Border around the smallmap.
 	WID_SM_MAP,            ///< Panel containing the smallmap.
diff --git a/src/widgets/station_widget.h b/src/widgets/station_widget.h
index 491505e430..4ed97af79c 100644
--- a/src/widgets/station_widget.h
+++ b/src/widgets/station_widget.h
@@ -11,7 +11,7 @@
 #define WIDGETS_STATION_WIDGET_H
 
 /** Widgets of the #StationViewWindow class. */
-enum StationViewWidgets {
+enum StationViewWidgets : WidgetID {
 	WID_SV_CAPTION,            ///< Caption of the window.
 	WID_SV_GROUP,              ///< label for "group by"
 	WID_SV_GROUP_BY,           ///< 'Group by' button
@@ -32,7 +32,7 @@ enum StationViewWidgets {
 };
 
 /** Widgets of the #CompanyStationsWindow class. */
-enum StationListWidgets {
+enum StationListWidgets : WidgetID {
 	/* Name starts with ST instead of S, because of collision with SaveLoadWidgets */
 	WID_STL_CAPTION,        ///< Caption of the window.
 	WID_STL_LIST,           ///< The main panel, list of stations.
@@ -56,7 +56,7 @@ enum StationListWidgets {
 };
 
 /** Widgets of the #SelectStationWindow class. */
-enum JoinStationWidgets {
+enum JoinStationWidgets : WidgetID {
 	WID_JS_CAPTION,   // Caption of the window.
 	WID_JS_PANEL,     // Main panel.
 	WID_JS_SCROLLBAR, // Scrollbar of the panel.
diff --git a/src/widgets/statusbar_widget.h b/src/widgets/statusbar_widget.h
index bb8149e461..dae3efb5b9 100644
--- a/src/widgets/statusbar_widget.h
+++ b/src/widgets/statusbar_widget.h
@@ -11,7 +11,7 @@
 #define WIDGETS_STATUSBAR_WIDGET_H
 
 /** Widgets of the #StatusBarWindow class. */
-enum StatusbarWidgets {
+enum StatusbarWidgets : WidgetID {
 	WID_S_LEFT,   ///< Left part of the statusbar; date is shown there.
 	WID_S_MIDDLE, ///< Middle part; current news or company name or *** SAVING *** or *** PAUSED ***.
 	WID_S_RIGHT,  ///< Right part; bank balance.
diff --git a/src/widgets/story_widget.h b/src/widgets/story_widget.h
index 3492aed419..ce3ffd5dff 100644
--- a/src/widgets/story_widget.h
+++ b/src/widgets/story_widget.h
@@ -12,7 +12,7 @@
 #define WIDGETS_STORY_WIDGET_H
 
 /** Widgets of the #GoalListWindow class. */
-enum StoryBookWidgets {
+enum StoryBookWidgets : WidgetID {
 	WID_SB_CAPTION,   ///< Caption of the window.
 	WID_SB_SEL_PAGE,  ///< Page selector.
 	WID_SB_PAGE_PANEL,///< Page body.
diff --git a/src/widgets/subsidy_widget.h b/src/widgets/subsidy_widget.h
index b3edd897c5..a2dfe8d1e8 100644
--- a/src/widgets/subsidy_widget.h
+++ b/src/widgets/subsidy_widget.h
@@ -11,7 +11,7 @@
 #define WIDGETS_SUBSIDY_WIDGET_H
 
 /** Widgets of the #SubsidyListWindow class. */
-enum SubsidyListWidgets {
+enum SubsidyListWidgets : WidgetID {
 	/* Name starts with SU instead of S, because of collision with SaveLoadWidgets. */
 	WID_SUL_PANEL,     ///< Main panel of window.
 	WID_SUL_SCROLLBAR, ///< Scrollbar of panel.
diff --git a/src/widgets/terraform_widget.h b/src/widgets/terraform_widget.h
index 777a2beb64..6b5796f9b5 100644
--- a/src/widgets/terraform_widget.h
+++ b/src/widgets/terraform_widget.h
@@ -11,7 +11,7 @@
 #define WIDGETS_TERRAFORM_WIDGET_H
 
 /** Widgets of the #TerraformToolbarWindow class. */
-enum TerraformToolbarWidgets {
+enum TerraformToolbarWidgets : WidgetID {
 	WID_TT_SHOW_PLACE_OBJECT,                 ///< Should the place object button be shown?
 	WID_TT_BUTTONS_START,                     ///< Start of pushable buttons.
 	WID_TT_LOWER_LAND = WID_TT_BUTTONS_START, ///< Lower land button.
@@ -27,7 +27,7 @@ enum TerraformToolbarWidgets {
 };
 
 /** Widgets of the #ScenarioEditorLandscapeGenerationWindow class. */
-enum EditorTerraformToolbarWidgets {
+enum EditorTerraformToolbarWidgets : WidgetID {
 	WID_ETT_SHOW_PLACE_DESERT,                   ///< Should the place desert button be shown?
 	WID_ETT_START,                               ///< Used for iterations.
 	WID_ETT_DOTS = WID_ETT_START,                ///< Invisible widget for rendering the terraform size on.
diff --git a/src/widgets/timetable_widget.h b/src/widgets/timetable_widget.h
index 15c44f33c5..2136b1ba2f 100644
--- a/src/widgets/timetable_widget.h
+++ b/src/widgets/timetable_widget.h
@@ -11,7 +11,7 @@
 #define WIDGETS_TIMETABLE_WIDGET_H
 
 /** Widgets of the #TimetableWindow class. */
-enum VehicleTimetableWidgets {
+enum VehicleTimetableWidgets : WidgetID {
 	WID_VT_CAPTION,                     ///< Caption of the window.
 	WID_VT_ORDER_VIEW,                  ///< Order view.
 	WID_VT_TIMETABLE_PANEL,             ///< Timetable panel.
diff --git a/src/widgets/toolbar_widget.h b/src/widgets/toolbar_widget.h
index d68de49700..36b53516af 100644
--- a/src/widgets/toolbar_widget.h
+++ b/src/widgets/toolbar_widget.h
@@ -11,7 +11,7 @@
 #define WIDGETS_TOOLBAR_WIDGET_H
 
 /** Widgets of the #MainToolbarWindow class. */
-enum ToolbarNormalWidgets {
+enum ToolbarNormalWidgets : WidgetID {
 	WID_TN_PAUSE,         ///< Pause the game.
 	WID_TN_FAST_FORWARD,  ///< Fast forward the game.
 	WID_TN_SETTINGS,      ///< Settings menu.
@@ -49,7 +49,7 @@ enum ToolbarNormalWidgets {
 };
 
 /** Widgets of the #ScenarioEditorToolbarWindow class. */
-enum ToolbarEditorWidgets {
+enum ToolbarEditorWidgets : WidgetID {
 	WID_TE_PAUSE,         ///< Pause the game.
 	WID_TE_FAST_FORWARD,  ///< Fast forward the game.
 	WID_TE_SETTINGS,      ///< Settings menu.
diff --git a/src/widgets/town_widget.h b/src/widgets/town_widget.h
index f16a8a585e..f8d6c84ba0 100644
--- a/src/widgets/town_widget.h
+++ b/src/widgets/town_widget.h
@@ -11,7 +11,7 @@
 #define WIDGETS_TOWN_WIDGET_H
 
 /** Widgets of the #TownDirectoryWindow class. */
-enum TownDirectoryWidgets {
+enum TownDirectoryWidgets : WidgetID {
 	WID_TD_SORT_ORDER,       ///< Direction of sort dropdown.
 	WID_TD_SORT_CRITERIA,    ///< Criteria of sort dropdown.
 	WID_TD_FILTER,           ///< Filter of name.
@@ -21,7 +21,7 @@ enum TownDirectoryWidgets {
 };
 
 /** Widgets of the #TownAuthorityWindow class. */
-enum TownAuthorityWidgets {
+enum TownAuthorityWidgets : WidgetID {
 	WID_TA_CAPTION,      ///< Caption of window.
 	WID_TA_ZONE_BUTTON,  ///< Turn on/off showing local authority zone.
 	WID_TA_RATING_INFO,  ///< Overview with ratings for each company.
@@ -32,7 +32,7 @@ enum TownAuthorityWidgets {
 };
 
 /** Widgets of the #TownViewWindow class. */
-enum TownViewWidgets {
+enum TownViewWidgets : WidgetID {
 	WID_TV_CAPTION,        ///< Caption of window.
 	WID_TV_VIEWPORT,       ///< View of the center of the town.
 	WID_TV_INFO,           ///< General information about the town.
@@ -45,7 +45,7 @@ enum TownViewWidgets {
 };
 
 /** Widgets of the #FoundTownWindow class. */
-enum TownFoundingWidgets {
+enum TownFoundingWidgets : WidgetID {
 	WID_TF_NEW_TOWN,          ///< Create a new town.
 	WID_TF_RANDOM_TOWN,       ///< Randomly place a town.
 	WID_TF_MANY_RANDOM_TOWNS, ///< Randomly place many towns.
diff --git a/src/widgets/transparency_widget.h b/src/widgets/transparency_widget.h
index a187eeaa47..15cf7b731d 100644
--- a/src/widgets/transparency_widget.h
+++ b/src/widgets/transparency_widget.h
@@ -11,7 +11,7 @@
 #define WIDGETS_TRANSPARENCY_WIDGET_H
 
 /** Widgets of the #TransparenciesWindow class. */
-enum TransparencyToolbarWidgets {
+enum TransparencyToolbarWidgets : WidgetID {
 	/* Button row. */
 	WID_TT_BEGIN,                    ///< First toggle button.
 	WID_TT_SIGNS = WID_TT_BEGIN,     ///< Signs background transparency toggle button.
diff --git a/src/widgets/tree_widget.h b/src/widgets/tree_widget.h
index 2cfc38ad40..ba22199d65 100644
--- a/src/widgets/tree_widget.h
+++ b/src/widgets/tree_widget.h
@@ -11,7 +11,7 @@
 #define WIDGETS_TREE_WIDGET_H
 
 /** Widgets of the #BuildTreesWindow class. */
-enum BuildTreesWidgets {
+enum BuildTreesWidgets : WidgetID {
 	WID_BT_TYPE_RANDOM,     ///< Button to build random type of tree.
 	WID_BT_SE_PANE,         ///< Selection pane to show/hide scenario editor tools.
 	WID_BT_MODE_NORMAL,     ///< Select normal/rectangle planting mode.
diff --git a/src/widgets/vehicle_widget.h b/src/widgets/vehicle_widget.h
index 8e960bcb79..e74011b9cb 100644
--- a/src/widgets/vehicle_widget.h
+++ b/src/widgets/vehicle_widget.h
@@ -11,7 +11,7 @@
 #define WIDGETS_VEHICLE_WIDGET_H
 
 /** Widgets of the #VehicleViewWindow class. */
-enum VehicleViewWidgets {
+enum VehicleViewWidgets : WidgetID {
 	WID_VV_CAPTION,            ///< Caption of window.
 	WID_VV_VIEWPORT,           ///< Viewport widget.
 	WID_VV_START_STOP,         ///< Start or stop this vehicle, and show information about the current state.
@@ -31,7 +31,7 @@ enum VehicleViewWidgets {
 };
 
 /** Widgets of the #RefitWindow class. */
-enum VehicleRefitWidgets {
+enum VehicleRefitWidgets : WidgetID {
 	WID_VR_CAPTION,               ///< Caption of window.
 	WID_VR_VEHICLE_PANEL_DISPLAY, ///< Display with a representation of the vehicle to refit.
 	WID_VR_SHOW_HSCROLLBAR,       ///< Selection widget for the horizontal scrollbar.
@@ -44,7 +44,7 @@ enum VehicleRefitWidgets {
 };
 
 /** Widgets of the #VehicleDetailsWindow class. */
-enum VehicleDetailsWidgets {
+enum VehicleDetailsWidgets : WidgetID {
 	WID_VD_CAPTION,                     ///< Caption of window.
 	WID_VD_TOP_DETAILS,                 ///< Panel with generic details.
 	WID_VD_INCREASE_SERVICING_INTERVAL, ///< Increase the servicing interval.
@@ -61,7 +61,7 @@ enum VehicleDetailsWidgets {
 };
 
 /** Widgets of the #VehicleListWindow class. */
-enum VehicleListWidgets {
+enum VehicleListWidgets : WidgetID {
 	WID_VL_CAPTION,                  ///< Caption of window (for non shared orders windows).
 	WID_VL_CAPTION_SHARED_ORDERS,    ///< Caption of window (for shared orders windows).
 	WID_VL_CAPTION_SELECTION,        ///< Selection for caption.
diff --git a/src/widgets/viewport_widget.h b/src/widgets/viewport_widget.h
index 81a6983e89..b83d3c55e3 100644
--- a/src/widgets/viewport_widget.h
+++ b/src/widgets/viewport_widget.h
@@ -11,7 +11,7 @@
 #define WIDGETS_VIEWPORT_WIDGET_H
 
 /** Widgets of the #ExtraViewportWindow class. */
-enum ExtraViewportWidgets {
+enum ExtraViewportWidgets : WidgetID {
 	WID_EV_CAPTION,      ///< Caption of window.
 	WID_EV_VIEWPORT,     ///< The viewport.
 	WID_EV_ZOOM_IN,      ///< Zoom in.
diff --git a/src/widgets/waypoint_widget.h b/src/widgets/waypoint_widget.h
index bca6082bd1..f942b51bc5 100644
--- a/src/widgets/waypoint_widget.h
+++ b/src/widgets/waypoint_widget.h
@@ -11,7 +11,7 @@
 #define WIDGETS_WAYPOINT_WIDGET_H
 
 /** Widgets of the #WaypointWindow class. */
-enum WaypointWidgets {
+enum WaypointWidgets : WidgetID {
 	WID_W_CAPTION,       ///< Caption of window.
 	WID_W_VIEWPORT,      ///< The viewport on this waypoint.
 	WID_W_CENTER_VIEW,   ///< Center the main view on this waypoint.