diff --git a/src/display.cpp b/src/display.cpp
index 3bb479ec2ebf..adca2577e422 100644
--- a/src/display.cpp
+++ b/src/display.cpp
@@ -72,7 +72,6 @@ namespace {
 
 	const unsigned int MinZoom = zoom_levels.front();
 	const unsigned int MaxZoom = zoom_levels.back();
-	size_t sunset_delay = 0;
 
 	bool benchmark = false;
 
@@ -1312,12 +1311,6 @@ void display::drawing_buffer_clear()
 	drawing_buffer_.clear();
 }
 
-void display::sunset(const size_t delay)
-{
-	// This allow both parametric and toggle use
-	sunset_delay = (sunset_delay == 0 && delay == 0) ? 3 : delay;
-}
-
 void display::toggle_benchmark()
 {
 	benchmark = !benchmark;
@@ -1336,15 +1329,6 @@ void display::flip()
 
 	surface& frameBuffer = video().getSurface();
 
-	// This is just the debug function "sunset" to progressively darken the map area
-	static size_t sunset_timer = 0;
-	if (sunset_delay && ++sunset_timer > sunset_delay) {
-		sunset_timer = 0;
-		SDL_Rect r = map_outside_area(); // Use frameBuffer to also test the UI
-		const Uint32 color =  SDL_MapRGBA(video().getSurface()->format,0,0,0,SDL_ALPHA_OPAQUE);
-		// Adjust the alpha if you want to balance cpu-cost / smooth sunset
-		sdl::fill_rect_alpha(r, color, 1, frameBuffer);
-	}
 	font::draw_floating_labels(frameBuffer);
 	events::raise_volatile_draw_event();
 
diff --git a/src/display.hpp b/src/display.hpp
index 8159cd226b79..ac5fbd2f7ca5 100644
--- a/src/display.hpp
+++ b/src/display.hpp
@@ -437,15 +437,6 @@ class display : public filter_context, public video2::draw_layering
 	void clear_mouseover_hex_overlay()
 		{ mouseover_hex_overlay_ = nullptr; }
 
-	/**
-	 * Debug function to toggle the "sunset" mode.
-	 * The map area become progressively darker,
-	 * except where hexes are refreshed.
-	 * delay is the number of frames between each darkening
-	 * (0 to toggle).
-	 */
-	static void sunset(const size_t delay = 0);
-
 	/** Toggle to continuously redraw the screen. */
 	static void toggle_benchmark();
 
diff --git a/src/gui/widgets/window.cpp b/src/gui/widgets/window.cpp
index 7eac195a4e63..5978e734a930 100644
--- a/src/gui/widgets/window.cpp
+++ b/src/gui/widgets/window.cpp
@@ -103,8 +103,6 @@ class builder_window : public builder_styled_widget
 } // namespace implementation
 REGISTER_WIDGET(window)
 
-unsigned window::sunset_ = 0;
-
 namespace
 {
 #ifdef DEBUG_WINDOW_LAYOUT_GRAPHS
@@ -746,18 +744,6 @@ void window::draw()
 	}
 
 	if (dirty_list_.empty()) {
-		if (sunset_) {
-			/** @todo should probably be moved to event::sdl_event_handler::draw. */
-			static unsigned i = 0;
-			if (++i % sunset_ == 0) {
-				SDL_Rect r = sdl::create_rect(
-					0, 0, frame_buffer->w, frame_buffer->h);
-				const Uint32 color
-					= SDL_MapRGBA(frame_buffer->format, 0, 0, 0, SDL_ALPHA_OPAQUE);
-
-				sdl::fill_rect_alpha(r, color, 1, frame_buffer);
-			}
-		}
 		return;
 	}
 
diff --git a/src/gui/widgets/window.hpp b/src/gui/widgets/window.hpp
index ad7659ef1e96..14a617e5bccf 100644
--- a/src/gui/widgets/window.hpp
+++ b/src/gui/widgets/window.hpp
@@ -440,11 +440,6 @@ class window : public panel, public cursor::setter
 		click_dismiss_ = click_dismiss;
 	}
 
-	static void set_sunset(const unsigned interval)
-	{
-		sunset_ = interval ? interval : 5;
-	}
-
 	bool get_need_layout() const
 	{
 		return need_layout_;
@@ -612,15 +607,6 @@ class window : public panel, public cursor::setter
 	/** Disable the escape key see our setter for more info. */
 	bool escape_disabled_;
 
-	/**
-	 * Controls the sunset feature.
-	 *
-	 * If this value is not 0 it will darken the entire screen every
-	 * sunset_th drawing request that nothing has been modified. It's a debug
-	 * feature.
-	 */
-	static unsigned sunset_;
-
 	/**
 	 * Helper struct to force widgets the have the same size.
 	 *
diff --git a/src/menu_events.cpp b/src/menu_events.cpp
index 6833a95f6187..4ef6f0fd7b4f 100644
--- a/src/menu_events.cpp
+++ b/src/menu_events.cpp
@@ -1008,7 +1008,6 @@ class console_handler : public map_command_handler<console_handler>, private cha
 		void do_control();
 		void do_controller();
 		void do_clear();
-		void do_sunset();
 		void do_foreground();
 		void do_layers();
 		void do_fps();
@@ -1094,8 +1093,6 @@ class console_handler : public map_command_handler<console_handler>, private cha
 				_("Query the controller status of a side."), _("<side>"));
 			register_command("clear", &console_handler::do_clear,
 				_("Clear chat history."));
-			register_command("sunset", &console_handler::do_sunset,
-				_("Visualize the screen refresh procedure."), "", "D");
 			register_command("foreground", &console_handler::do_foreground,
 				_("Debug foreground terrain."), "", "D");
 			register_command("layers", &console_handler::do_layers,
@@ -1489,11 +1486,7 @@ void console_handler::do_controller()
 void console_handler::do_clear() {
 	menu_handler_.gui_->get_chat_manager().clear_chat_messages();
 }
-void console_handler::do_sunset() {
-	int delay = lexical_cast_default<int>(get_data());
-	menu_handler_.gui_->sunset(delay);
-	gui2::window::set_sunset(delay);
-}
+
 void console_handler::do_foreground() {
 	menu_handler_.gui_->toggle_debug_foreground();
 }