diff --git a/src/gui/dialogs/drop_down_menu.cpp b/src/gui/dialogs/drop_down_menu.cpp
index 7dd1451c4196..937d220324c8 100644
--- a/src/gui/dialogs/drop_down_menu.cpp
+++ b/src/gui/dialogs/drop_down_menu.cpp
@@ -139,8 +139,7 @@ void drop_down_menu::pre_show(window& window)
 		find_widget<toggle_panel>(&new_row, "panel", false).set_tooltip(entry["tooltip"]);
 
 		if(entry.has_attribute("image")) {
-			image* img = new image();
-			img->set_definition("default");
+			image* img = build_single_widget_instance<image>("image");
 			img->set_label(entry["image"]);
 
 			grid* mi_grid = dynamic_cast<grid*>(new_row.find("menu_item", false));
@@ -150,8 +149,7 @@ void drop_down_menu::pre_show(window& window)
 		}
 
 		if(entry.has_attribute("checkbox")) {
-			toggle_button* checkbox = new toggle_button();
-			checkbox->set_definition("default");
+			toggle_button* checkbox = build_single_widget_instance<toggle_button>("toggle_button");
 			checkbox->set_id("checkbox");
 			checkbox->set_value_bool(entry["checkbox"].to_bool(false));
 
diff --git a/src/gui/dialogs/preferences_dialog.cpp b/src/gui/dialogs/preferences_dialog.cpp
index 60be889a88cf..087b1f6f1ff6 100644
--- a/src/gui/dialogs/preferences_dialog.cpp
+++ b/src/gui/dialogs/preferences_dialog.cpp
@@ -604,8 +604,7 @@ void preferences_dialog::post_build(window& window)
 			}
 
 			case ADVANCED_PREF_TYPE::SLIDER: {
-				slider* setter_widget = new slider();
-				setter_widget->set_definition("minimal");
+				slider* setter_widget = build_single_widget_instance<slider>("slider", config {"definition", "minimal"});
 				setter_widget->set_id("setter");
 				// Maximum must be set first or this will assert
 				setter_widget->set_maximum_value(option["max"].to_int());
@@ -647,8 +646,7 @@ void preferences_dialog::post_build(window& window)
 				const unsigned selected = std::find(option_ids.begin(), option_ids.end(),
 					get(pref_name, option["default"].str())) - option_ids.begin();
 
-				menu_button* setter_widget = new menu_button();
-				setter_widget->set_definition("default");
+				menu_button* setter_widget = build_single_widget_instance<menu_button>("menu_button");
 				setter_widget->set_id("setter");
 
 				details_grid.swap_child("setter", setter_widget, true);
@@ -671,8 +669,7 @@ void preferences_dialog::post_build(window& window)
 			case ADVANCED_PREF_TYPE::SPECIAL: {
 				//main_grid->remove_child("setter");
 
-				image* value_widget = new image();
-				value_widget->set_definition("default");
+				image* value_widget = build_single_widget_instance<image>("image");
 				value_widget->set_label("icons/arrows/arrows_blank_right_25.png~CROP(3,3,18,18)");
 
 				main_grid->swap_child("value", value_widget, true);
diff --git a/src/gui/widgets/addon_list.cpp b/src/gui/widgets/addon_list.cpp
index fa5dad887fcd..cd8c5bc4a68d 100644
--- a/src/gui/widgets/addon_list.cpp
+++ b/src/gui/widgets/addon_list.cpp
@@ -39,6 +39,18 @@ namespace gui2
 
 REGISTER_WIDGET(addon_list)
 
+addon_list::addon_list(const implementation::builder_addon_list& builder)
+	: container_base(builder, get_control_type())
+	, addon_vector_()
+	, install_status_visibility_(visibility::visible)
+	, install_buttons_visibility_(visibility::invisible)
+	, install_function_()
+	, uninstall_function_()
+	, publish_function_()
+	, delete_function_()
+{
+}
+
 static color_t color_outdated {255, 127, 0};
 
 std::string addon_list::colorify_addon_state_string(const std::string& str, ADDON_STATUS state, bool verbose)
@@ -439,9 +451,7 @@ builder_addon_list::builder_addon_list(const config& cfg) :
 
 widget* builder_addon_list::build() const
 {
-	addon_list* widget = new addon_list();
-
-	init_control(widget);
+	addon_list* widget = new addon_list(*this);
 
 	DBG_GUI_G << "Window builder: placed add-on list '" << id <<
 		"' with definition '" << definition << "'.\n";
diff --git a/src/gui/widgets/addon_list.hpp b/src/gui/widgets/addon_list.hpp
index cc8b41e591bb..edda93d2972f 100644
--- a/src/gui/widgets/addon_list.hpp
+++ b/src/gui/widgets/addon_list.hpp
@@ -38,16 +38,7 @@ class addon_list : public container_base
 	friend struct implementation::builder_addon_list;
 
 public:
-	addon_list()
-		: container_base()
-		, addon_vector_()
-		, install_status_visibility_(visibility::visible)
-		, install_buttons_visibility_(visibility::invisible)
-		, install_function_()
-		, uninstall_function_()
-		, publish_function_()
-		, delete_function_()
-	{}
+	explicit addon_list(const implementation::builder_addon_list& builder);
 
 	/** Special retval for the toggle panels in the addons list */
 	static const int DEFAULT_ACTION_RETVAL = 200;
diff --git a/src/gui/widgets/button.cpp b/src/gui/widgets/button.cpp
index 59d305b06698..75d6a065ef41 100644
--- a/src/gui/widgets/button.cpp
+++ b/src/gui/widgets/button.cpp
@@ -40,7 +40,11 @@ namespace gui2
 
 REGISTER_WIDGET(button)
 
-button::button() : styled_widget(), clickable_item(), state_(ENABLED), retval_(0)
+button::button(const implementation::builder_button& builder)
+	: styled_widget(builder, get_control_type())
+	, clickable_item()
+	, state_(ENABLED)
+	, retval_(0)
 {
 	connect_signal<event::MOUSE_ENTER>(
 			std::bind(&button::signal_handler_mouse_enter, this, _2, _3));
@@ -246,9 +250,7 @@ builder_button::builder_button(const config& cfg)
 
 widget* builder_button::build() const
 {
-	button* widget = new button();
-
-	init_control(widget);
+	button* widget = new button(*this);
 
 	widget->set_retval(get_retval(retval_id_, retval_, id));
 
diff --git a/src/gui/widgets/button.hpp b/src/gui/widgets/button.hpp
index d361d564cfee..73cf093b0e35 100644
--- a/src/gui/widgets/button.hpp
+++ b/src/gui/widgets/button.hpp
@@ -22,6 +22,10 @@
 
 namespace gui2
 {
+namespace implementation
+{
+	struct builder_button;
+}
 
 // ------------ WIDGET -----------{
 
@@ -31,7 +35,7 @@ namespace gui2
 class button : public styled_widget, public clickable_item
 {
 public:
-	button();
+	explicit button(const implementation::builder_button& builder);
 
 	/***** ***** ***** ***** Inherited ***** ***** ***** *****/
 
diff --git a/src/gui/widgets/chatbox.cpp b/src/gui/widgets/chatbox.cpp
index 85dd2ad80548..45b8d2b8be2d 100644
--- a/src/gui/widgets/chatbox.cpp
+++ b/src/gui/widgets/chatbox.cpp
@@ -52,8 +52,8 @@ namespace gui2
 
 REGISTER_WIDGET(chatbox)
 
-chatbox::chatbox()
-	: container_base()
+chatbox::chatbox(const implementation::builder_chatbox& builder)
+	: container_base(builder, get_control_type())
 	, roomlistbox_(nullptr)
 	, chat_log_container_(nullptr)
 	, chat_input_(nullptr)
@@ -758,9 +758,7 @@ builder_chatbox::builder_chatbox(const config& cfg)
 
 widget* builder_chatbox::build() const
 {
-	chatbox* widget = new chatbox();
-
-	init_control(widget);
+	chatbox* widget = new chatbox(*this);
 
 	DBG_GUI_G << "Window builder: placed unit preview pane '" << id
 			  << "' with definition '" << definition << "'.\n";
diff --git a/src/gui/widgets/chatbox.hpp b/src/gui/widgets/chatbox.hpp
index c27d145f83ae..d278b89aefa5 100644
--- a/src/gui/widgets/chatbox.hpp
+++ b/src/gui/widgets/chatbox.hpp
@@ -57,7 +57,7 @@ class chatbox : public container_base, public events::chat_handler
 	friend struct implementation::builder_chatbox;
 
 public:
-	chatbox();
+	explicit chatbox(const implementation::builder_chatbox& builder);
 
 	/** See @ref styled_widget::set_active. */
 	virtual void set_active(const bool active) override;
diff --git a/src/gui/widgets/container_base.cpp b/src/gui/widgets/container_base.cpp
index 07c9243a2a8c..0121cbeb898e 100644
--- a/src/gui/widgets/container_base.cpp
+++ b/src/gui/widgets/container_base.cpp
@@ -28,8 +28,9 @@
 namespace gui2
 {
 
-container_base::container_base()
-	: styled_widget(), grid_()
+container_base::container_base(const implementation::builder_styled_widget& builder, const std::string& control_type)
+	: styled_widget(builder, control_type)
+	, grid_()
 {
 	grid_.set_parent(this);
 	connect_signal<event::REQUEST_PLACEMENT>(
diff --git a/src/gui/widgets/container_base.hpp b/src/gui/widgets/container_base.hpp
index f75c8b81bb8d..1a5520e9cbcc 100644
--- a/src/gui/widgets/container_base.hpp
+++ b/src/gui/widgets/container_base.hpp
@@ -20,6 +20,10 @@
 
 namespace gui2
 {
+namespace implementation
+{
+struct builder_styled_widget;
+}
 
 /**
  * A generic container base class.
@@ -33,7 +37,7 @@ class container_base : public styled_widget
 	friend class debug_layout_graph;
 
 public:
-	container_base();
+	explicit container_base(const implementation::builder_styled_widget& builder, const std::string& control_type);
 
 	/**
 	 * Returns the client rect.
diff --git a/src/gui/widgets/drawing.cpp b/src/gui/widgets/drawing.cpp
index 0b4c60c17b21..80dba9cfa905 100644
--- a/src/gui/widgets/drawing.cpp
+++ b/src/gui/widgets/drawing.cpp
@@ -31,6 +31,12 @@ namespace gui2
 
 REGISTER_WIDGET(drawing)
 
+drawing::drawing(const implementation::builder_drawing& builder)
+	: styled_widget(builder, get_control_type())
+	, best_size_(0, 0)
+{
+}
+
 point drawing::calculate_best_size() const
 {
 	return best_size_ != point() ? best_size_
@@ -177,9 +183,7 @@ builder_drawing::builder_drawing(const config& cfg)
 
 widget* builder_drawing::build() const
 {
-	drawing* widget = new drawing();
-
-	init_control(widget);
+	drawing* widget = new drawing(*this);
 
 	const wfl::map_formula_callable& size = get_screen_size_variables();
 
diff --git a/src/gui/widgets/drawing.hpp b/src/gui/widgets/drawing.hpp
index dbb08f4bfc1e..1af9d6409685 100644
--- a/src/gui/widgets/drawing.hpp
+++ b/src/gui/widgets/drawing.hpp
@@ -23,7 +23,10 @@ class config;
 
 namespace gui2
 {
-
+namespace implementation
+{
+	struct builder_drawing;
+}
 // ------------ WIDGET -----------{
 
 /**
@@ -35,9 +38,7 @@ namespace gui2
 class drawing : public styled_widget
 {
 public:
-	drawing() : styled_widget(), best_size_(0, 0)
-	{
-	}
+	explicit drawing(const implementation::builder_drawing& builder);
 
 	canvas& get_drawing_canvas()
 	{
diff --git a/src/gui/widgets/horizontal_scrollbar.cpp b/src/gui/widgets/horizontal_scrollbar.cpp
index 9448e6a0c4dc..73c3bfc66914 100644
--- a/src/gui/widgets/horizontal_scrollbar.cpp
+++ b/src/gui/widgets/horizontal_scrollbar.cpp
@@ -33,6 +33,11 @@ namespace gui2
 
 REGISTER_WIDGET(horizontal_scrollbar)
 
+horizontal_scrollbar::horizontal_scrollbar(const implementation::builder_horizontal_scrollbar& builder)
+	: scrollbar_base(builder, get_control_type())
+{
+}
+
 unsigned horizontal_scrollbar::minimum_positioner_length() const
 {
 	const auto conf = cast_config_to<horizontal_scrollbar_definition>();
@@ -217,9 +222,9 @@ builder_horizontal_scrollbar::builder_horizontal_scrollbar(const config& cfg)
 
 widget* builder_horizontal_scrollbar::build() const
 {
-	horizontal_scrollbar* widget = new horizontal_scrollbar();
+	horizontal_scrollbar* widget = new horizontal_scrollbar(*this);
 
-	init_control(widget);
+	widget->finalize_setup();
 
 	DBG_GUI_G << "Window builder:"
 			  << " placed horizontal scrollbar '" << id << "' with definition '"
diff --git a/src/gui/widgets/horizontal_scrollbar.hpp b/src/gui/widgets/horizontal_scrollbar.hpp
index c8688704da42..93eba3ad8e0d 100644
--- a/src/gui/widgets/horizontal_scrollbar.hpp
+++ b/src/gui/widgets/horizontal_scrollbar.hpp
@@ -21,16 +21,20 @@
 
 namespace gui2
 {
+namespace implementation
+{
+struct builder_horizontal_scrollbar;
+}
 
 // ------------ WIDGET -----------{
 
 /** A horizontal scrollbar. */
 class horizontal_scrollbar : public scrollbar_base
 {
+	friend struct implementation::builder_horizontal_scrollbar;
+
 public:
-	horizontal_scrollbar() : scrollbar_base()
-	{
-	}
+	explicit horizontal_scrollbar(const implementation::builder_horizontal_scrollbar& builder);
 
 private:
 	/** Inherited from tscrollbar. */
diff --git a/src/gui/widgets/image.cpp b/src/gui/widgets/image.cpp
index f2a9983a678a..f2ddbec91b16 100644
--- a/src/gui/widgets/image.cpp
+++ b/src/gui/widgets/image.cpp
@@ -36,6 +36,11 @@ namespace gui2
 
 REGISTER_WIDGET(image)
 
+image::image(const implementation::builder_image& builder)
+	: styled_widget(builder, get_control_type())
+{
+}
+
 point image::calculate_best_size() const
 {
 	surface image(::image::get_image(::image::locator(get_label())));
@@ -168,9 +173,7 @@ builder_image::builder_image(const config& cfg) : builder_styled_widget(cfg)
 
 widget* builder_image::build() const
 {
-	image* widget = new image();
-
-	init_control(widget);
+	image* widget = new image(*this);
 
 	DBG_GUI_G << "Window builder: placed image '" << id << "' with definition '"
 			  << definition << "'.\n";
diff --git a/src/gui/widgets/image.hpp b/src/gui/widgets/image.hpp
index 74684a508376..ac46804a9647 100644
--- a/src/gui/widgets/image.hpp
+++ b/src/gui/widgets/image.hpp
@@ -21,6 +21,10 @@
 
 namespace gui2
 {
+namespace implementation
+{
+	struct builder_image;
+}
 
 // ------------ WIDGET -----------{
 
@@ -28,9 +32,7 @@ namespace gui2
 class image : public styled_widget
 {
 public:
-	image() : styled_widget()
-	{
-	}
+	explicit image(const implementation::builder_image& builder);
 
 	/**
 	 * Wrapper for set_label.
diff --git a/src/gui/widgets/label.cpp b/src/gui/widgets/label.cpp
index a51f05f0b69c..b8faf25bfd5a 100644
--- a/src/gui/widgets/label.cpp
+++ b/src/gui/widgets/label.cpp
@@ -40,15 +40,15 @@ namespace gui2
 
 REGISTER_WIDGET(label)
 
-label::label()
-		: styled_widget()
-		, state_(ENABLED)
-		, can_wrap_(false)
-		, characters_per_line_(0)
-		, link_aware_(false)
-		, link_color_(color_t::from_hex_string("ffff00"))
-		, can_shrink_(false)
-		, text_alpha_(255)
+label::label(const implementation::builder_label& builder)
+	: styled_widget(builder, get_control_type())
+	, state_(ENABLED)
+	, can_wrap_(false)
+	, characters_per_line_(0)
+	, link_aware_(false)
+	, link_color_(color_t::from_hex_string("ffff00"))
+	, can_shrink_(false)
+	, text_alpha_(255)
 {
 	connect_signal<event::LEFT_BUTTON_CLICK>(std::bind(&label::signal_handler_left_button_click, this, _2, _3));
 	connect_signal<event::RIGHT_BUTTON_CLICK>(std::bind(&label::signal_handler_right_button_click, this, _2, _3));
@@ -147,18 +147,6 @@ const std::string& label::get_control_type() const
 	return type;
 }
 
-void label::load_config_extra()
-{
-	assert(config());
-
-	const auto conf = cast_config_to<label_definition>();
-	assert(conf);
-
-	set_link_aware(conf->link_aware);
-	set_link_color(conf->link_color);
-}
-
-
 void label::signal_handler_left_button_click(const event::ui_event /* event */, bool & handled)
 {
 	DBG_GUI_E << "label click" << std::endl;
@@ -334,15 +322,18 @@ builder_label::builder_label(const config& cfg)
 
 widget* builder_label::build() const
 {
-	label* lbl = new label();
+	label* lbl = new label(*this);
 
-	init_control(lbl);
+	const auto conf = lbl->cast_config_to<label_definition>();
+	assert(conf);
 
 	lbl->set_can_wrap(wrap);
 	lbl->set_characters_per_line(characters_per_line);
 	lbl->set_text_alignment(text_alignment);
 	lbl->set_text_alpha(ALPHA_OPAQUE);
 	lbl->set_can_shrink(can_shrink);
+	lbl->set_link_aware(conf->link_aware);
+	lbl->set_link_color(conf->link_color);
 
 	DBG_GUI_G << "Window builder: placed label '" << id << "' with definition '"
 			  << definition << "'.\n";
diff --git a/src/gui/widgets/label.hpp b/src/gui/widgets/label.hpp
index b04d03080d96..25923b4529fa 100644
--- a/src/gui/widgets/label.hpp
+++ b/src/gui/widgets/label.hpp
@@ -21,14 +21,20 @@
 
 namespace gui2
 {
+namespace implementation
+{
+	struct builder_label;
+}
 
 // ------------ WIDGET -----------{
 
 /** Label showing a text. */
 class label : public styled_widget
 {
+	friend struct implementation::builder_label;
+
 public:
-	label();
+	explicit label(const implementation::builder_label& builder);
 
 	/** See @ref widget::can_wrap. */
 	virtual bool can_wrap() const override;
@@ -131,9 +137,6 @@ class label : public styled_widget
 	/** See @ref styled_widget::get_control_type. */
 	virtual const std::string& get_control_type() const override;
 
-	/** Inherited from styled_widget. */
-	void load_config_extra() override;
-
 	/***** ***** ***** signal handlers ***** ****** *****/
 
 	/**
diff --git a/src/gui/widgets/listbox.cpp b/src/gui/widgets/listbox.cpp
index a86225dd7bc8..a983fc922100 100644
--- a/src/gui/widgets/listbox.cpp
+++ b/src/gui/widgets/listbox.cpp
@@ -60,11 +60,12 @@ void callback_list_item_clicked(widget& caller)
 
 } // namespace
 
-listbox::listbox(const bool has_minimum,
-				   const bool has_maximum,
-				   const generator_base::placement placement,
-				   const bool select)
-	: scrollbar_container()
+listbox::listbox(const implementation::builder_styled_widget& builder,
+		const bool has_minimum,
+		const bool has_maximum,
+		const generator_base::placement placement,
+		const bool select)
+	: scrollbar_container(builder, get_control_type())
 	, generator_(generator_base::build(has_minimum, has_maximum, placement, select))
 	, is_horizontal_(placement == generator_base::horizontal_list)
 	, list_builder_(nullptr)
@@ -972,16 +973,14 @@ widget* builder_listbox::build() const
 	list_view* widget = new list_view(
 			true, true, generator_base::vertical_list, true, list_builder);
 
-	init_control(widget);
+	//init_control(widget);
 	if(!list_data.empty()) {
 		widget->append_rows(list_data);
 	}
 	return widget;
 #else
 	listbox* widget
-			= new listbox(has_minimum_, has_maximum_, generator_base::vertical_list, true);
-
-	init_control(widget);
+			= new listbox(*this, has_minimum_, has_maximum_, generator_base::vertical_list, true);
 
 	widget->set_list_builder(list_builder); // FIXME in finalize???
 
@@ -1095,16 +1094,14 @@ widget* builder_horizontal_listbox::build() const
 	list_view* widget = new list_view(
 			true, true, generator_base::horizontal_list, true, list_builder);
 
-	init_control(widget);
+	//init_control(widget);
 	if(!list_data.empty()) {
 		widget->append_rows(list_data);
 	}
 	return widget;
 #else
 	listbox* widget
-			= new listbox(has_minimum_, has_maximum_, generator_base::horizontal_list, true);
-
-	init_control(widget);
+			= new listbox(*this, has_minimum_, has_maximum_, generator_base::horizontal_list, true);
 
 	widget->set_list_builder(list_builder); // FIXME in finalize???
 
@@ -1218,16 +1215,14 @@ widget* builder_grid_listbox::build() const
 	list_view* widget = new list_view(
 			true, true, generator_base::grid, true, list_builder);
 
-	init_control(widget);
+	//init_control(widget);
 	if(!list_data.empty()) {
 		widget->append_rows(list_data);
 	}
 	return widget;
 #else
 	listbox* widget
-			= new listbox(has_minimum_, has_maximum_, generator_base::table, true);
-
-	init_control(widget);
+			= new listbox(*this, has_minimum_, has_maximum_, generator_base::table, true);
 
 	widget->set_list_builder(list_builder); // FIXME in finalize???
 
diff --git a/src/gui/widgets/listbox.hpp b/src/gui/widgets/listbox.hpp
index 4cee882801c5..22734d4cabab 100644
--- a/src/gui/widgets/listbox.hpp
+++ b/src/gui/widgets/listbox.hpp
@@ -35,6 +35,7 @@ namespace implementation
 struct builder_listbox;
 struct builder_horizontal_listbox;
 struct builder_grid_listbox;
+struct builder_styled_widget;
 }
 
 /** The listbox class. */
@@ -49,6 +50,8 @@ class listbox : public scrollbar_container
 	/**
 	 * Constructor.
 	 *
+	 * @param builder             The builder for the appropriate listbox
+	 *                            variant.
 	 * @param has_minimum         Does the listbox need to have one item
 	 *                            selected.
 	 * @param has_maximum         Can the listbox only have one item
@@ -57,10 +60,11 @@ class listbox : public scrollbar_container
 	 * @param select              Select an item when selected, if false it
 	 *                            changes the visible state instead.
 	 */
-	listbox(const bool has_minimum,
-			 const bool has_maximum,
-			 const generator_base::placement placement,
-			 const bool select);
+	listbox(const implementation::builder_styled_widget& builder,
+			const bool has_minimum,
+			const bool has_maximum,
+			const generator_base::placement placement,
+			const bool select);
 
 	/***** ***** ***** ***** Row handling. ***** ***** ****** *****/
 	/**
diff --git a/src/gui/widgets/menu_button.cpp b/src/gui/widgets/menu_button.cpp
index 586b2cee9ee1..55c14fe6ab69 100644
--- a/src/gui/widgets/menu_button.cpp
+++ b/src/gui/widgets/menu_button.cpp
@@ -37,8 +37,8 @@ namespace gui2
 
 REGISTER_WIDGET(menu_button)
 
-menu_button::menu_button()
-	: styled_widget()
+menu_button::menu_button(const implementation::builder_menu_button& builder)
+	: styled_widget(builder, get_control_type())
 	, selectable_item()
 	, state_(ENABLED)
 	, retval_(0)
@@ -309,9 +309,7 @@ builder_menu_button::builder_menu_button(const config& cfg)
 
 widget* builder_menu_button::build() const
 {
-	menu_button* widget = new menu_button();
-
-	init_control(widget);
+	menu_button* widget = new menu_button(*this);
 
 	widget->set_retval(get_retval(retval_id_, retval_, id));
 	if(!options_.empty()) {
diff --git a/src/gui/widgets/menu_button.hpp b/src/gui/widgets/menu_button.hpp
index 1b9aff48ead7..0eb5fcc31e19 100644
--- a/src/gui/widgets/menu_button.hpp
+++ b/src/gui/widgets/menu_button.hpp
@@ -28,6 +28,10 @@ class config;
 
 namespace gui2
 {
+namespace implementation
+{
+	struct builder_menu_button;
+}
 
 // ------------ WIDGET -----------{
 
@@ -37,7 +41,7 @@ namespace gui2
 class menu_button : public styled_widget, public selectable_item
 {
 public:
-	menu_button();
+	explicit menu_button(const implementation::builder_menu_button& builder);
 
 	/***** ***** ***** ***** Inherited ***** ***** ***** *****/
 
diff --git a/src/gui/widgets/minimap.cpp b/src/gui/widgets/minimap.cpp
index 92d2497e616c..3337d6f16129 100644
--- a/src/gui/widgets/minimap.cpp
+++ b/src/gui/widgets/minimap.cpp
@@ -47,6 +47,13 @@ namespace gui2
 
 REGISTER_WIDGET(minimap)
 
+minimap::minimap(const implementation::builder_minimap& builder)
+	: styled_widget(builder, get_control_type())
+	, map_data_()
+	, terrain_(nullptr)
+{
+}
+
 void minimap::set_active(const bool /*active*/)
 {
 	/* DO NOTHING */
@@ -325,9 +332,7 @@ builder_minimap::builder_minimap(const config& cfg) : builder_styled_widget(cfg)
 
 widget* builder_minimap::build() const
 {
-	minimap* widget = new minimap();
-
-	init_control(widget);
+	minimap* widget = new minimap(*this);
 
 	DBG_GUI_G << "Window builder: placed minimap '" << id
 			  << "' with definition '" << definition << "'.\n";
diff --git a/src/gui/widgets/minimap.hpp b/src/gui/widgets/minimap.hpp
index 63e0a6260aaf..de4c31df043a 100644
--- a/src/gui/widgets/minimap.hpp
+++ b/src/gui/widgets/minimap.hpp
@@ -23,6 +23,10 @@ class config;
 
 namespace gui2
 {
+namespace implementation
+{
+struct builder_minimap;
+}
 
 // ------------ WIDGET -----------{
 
@@ -35,9 +39,7 @@ namespace gui2
 class minimap : public styled_widget
 {
 public:
-	minimap() : styled_widget(), map_data_(), terrain_(nullptr)
-	{
-	}
+	explicit minimap(const implementation::builder_minimap& builder);
 
 	/***** ***** ***** ***** Inherited ***** ***** ***** *****/
 
diff --git a/src/gui/widgets/multi_page.cpp b/src/gui/widgets/multi_page.cpp
index 6fc79de78914..c4df0a97af7e 100644
--- a/src/gui/widgets/multi_page.cpp
+++ b/src/gui/widgets/multi_page.cpp
@@ -32,10 +32,10 @@ namespace gui2
 // ------------ WIDGET -----------{
 
 REGISTER_WIDGET(multi_page)
-multi_page::multi_page()
-	: container_base()
-	, generator_(
-			  generator_base::build(true, true, generator_base::independent, false))
+
+multi_page::multi_page(const implementation::builder_multi_page& builder)
+	: container_base(builder, get_control_type())
+	, generator_(generator_base::build(true, true, generator_base::independent, false))
 	, page_builders_()
 {
 }
@@ -292,9 +292,7 @@ builder_multi_page::builder_multi_page(const config& cfg)
 
 widget* builder_multi_page::build() const
 {
-	multi_page* widget = new multi_page();
-
-	init_control(widget);
+	multi_page* widget = new multi_page(*this);
 
 	widget->set_page_builders(builders);
 
diff --git a/src/gui/widgets/multi_page.hpp b/src/gui/widgets/multi_page.hpp
index 2e39b11fd0c7..e3a5900bb948 100644
--- a/src/gui/widgets/multi_page.hpp
+++ b/src/gui/widgets/multi_page.hpp
@@ -38,7 +38,7 @@ class multi_page : public container_base
 	friend class debug_layout_graph;
 
 public:
-	multi_page();
+	explicit multi_page(const implementation::builder_multi_page& builder);
 
 	/***** ***** ***** ***** Page handling. ***** ***** ****** *****/
 
diff --git a/src/gui/widgets/multimenu_button.cpp b/src/gui/widgets/multimenu_button.cpp
index 60695faead0d..c7cc77e39372 100644
--- a/src/gui/widgets/multimenu_button.cpp
+++ b/src/gui/widgets/multimenu_button.cpp
@@ -39,8 +39,8 @@ namespace gui2
 
 REGISTER_WIDGET(multimenu_button)
 
-multimenu_button::multimenu_button()
-	: styled_widget()
+multimenu_button::multimenu_button(const implementation::builder_multimenu_button& builder)
+	: styled_widget(builder, get_control_type())
 	, state_(ENABLED)
 	, retval_(0)
 	, values_()
@@ -353,9 +353,7 @@ builder_multimenu_button::builder_multimenu_button(const config& cfg)
 
 widget* builder_multimenu_button::build() const
 {
-	multimenu_button* widget = new multimenu_button();
-
-	init_control(widget);
+	multimenu_button* widget = new multimenu_button(*this);
 
 	widget->set_retval(get_retval(retval_id_, retval_, id));
 	widget->set_max_shown(max_shown_);
diff --git a/src/gui/widgets/multimenu_button.hpp b/src/gui/widgets/multimenu_button.hpp
index f4be46a0dc47..82f649a73a9f 100644
--- a/src/gui/widgets/multimenu_button.hpp
+++ b/src/gui/widgets/multimenu_button.hpp
@@ -28,6 +28,10 @@ class config;
 
 namespace gui2
 {
+namespace implementation
+{
+struct builder_multimenu_button;
+}
 
 // ------------ WIDGET -----------{
 
@@ -37,7 +41,7 @@ namespace gui2
 class multimenu_button : public styled_widget
 {
 public:
-	multimenu_button();
+	explicit multimenu_button(const implementation::builder_multimenu_button& builder);
 
 	/***** ***** ***** ***** Inherited ***** ***** ***** *****/
 
diff --git a/src/gui/widgets/panel.cpp b/src/gui/widgets/panel.cpp
index c655738f9660..e5cc1fd0e39a 100644
--- a/src/gui/widgets/panel.cpp
+++ b/src/gui/widgets/panel.cpp
@@ -35,6 +35,11 @@ namespace gui2
 
 REGISTER_WIDGET(panel)
 
+panel::panel(const implementation::builder_styled_widget& builder, const std::string& control_type)
+	: container_base(builder, control_type.empty() ? get_control_type() : control_type)
+{
+}
+
 SDL_Rect panel::get_client_rect() const
 {
 	const auto conf = cast_config_to<panel_definition>();
@@ -199,9 +204,7 @@ builder_panel::builder_panel(const config& cfg)
 
 widget* builder_panel::build() const
 {
-	panel* widget = new panel();
-
-	init_control(widget);
+	panel* widget = new panel(*this);
 
 	DBG_GUI_G << "Window builder: placed panel '" << id << "' with definition '"
 			  << definition << "'.\n";
diff --git a/src/gui/widgets/panel.hpp b/src/gui/widgets/panel.hpp
index bf94aed116b2..cbeaa7ba7f8d 100644
--- a/src/gui/widgets/panel.hpp
+++ b/src/gui/widgets/panel.hpp
@@ -21,6 +21,10 @@
 
 namespace gui2
 {
+namespace implementation
+{
+struct builder_panel;
+}
 
 // ------------ WIDGET -----------{
 
@@ -32,14 +36,11 @@ namespace gui2
  */
 class panel : public container_base
 {
-
 public:
 	/**
 	 * Constructor.
 	 */
-	panel() : container_base()
-	{
-	}
+	panel(const implementation::builder_styled_widget& builder, const std::string& control_type = "");
 
 	/** See @ref container_base::get_client_rect. */
 	virtual SDL_Rect get_client_rect() const override;
diff --git a/src/gui/widgets/password_box.cpp b/src/gui/widgets/password_box.cpp
index c6c21634b15e..b7298efe7228 100644
--- a/src/gui/widgets/password_box.cpp
+++ b/src/gui/widgets/password_box.cpp
@@ -37,6 +37,12 @@ namespace gui2
 
 REGISTER_WIDGET3(text_box_definition, password_box, "text_box_definition")
 
+password_box::password_box(const implementation::builder_password_box& builder)
+	: text_box(builder)
+	, real_value_()
+{
+}
+
 void password_box::set_value(const std::string& text)
 {
 	real_value_ = text;
@@ -129,9 +135,7 @@ builder_password_box::builder_password_box(const config& cfg)
 
 widget* builder_password_box::build() const
 {
-	password_box* widget = new password_box();
-
-	init_control(widget);
+	password_box* widget = new password_box(*this);
 
 	// A password box doesn't have a label but a text.
 	// It also has no history.
diff --git a/src/gui/widgets/password_box.hpp b/src/gui/widgets/password_box.hpp
index fe4a111b1fce..fc3355e10002 100644
--- a/src/gui/widgets/password_box.hpp
+++ b/src/gui/widgets/password_box.hpp
@@ -28,15 +28,17 @@
  */
 namespace gui2
 {
+namespace implementation
+{
+	struct builder_password_box;
+}
 
 // ------------ WIDGET -----------{
 
 class password_box : public text_box
 {
 public:
-	password_box() : text_box(), real_value_()
-	{
-	}
+	explicit password_box(const implementation::builder_password_box& builder);
 
 	/** Inherited from text_box_base. */
 	virtual void set_value(const std::string& text) override;
diff --git a/src/gui/widgets/progress_bar.cpp b/src/gui/widgets/progress_bar.cpp
index e0e505de1340..ff4da58b44dc 100644
--- a/src/gui/widgets/progress_bar.cpp
+++ b/src/gui/widgets/progress_bar.cpp
@@ -32,6 +32,14 @@ namespace gui2
 
 REGISTER_WIDGET(progress_bar)
 
+progress_bar::progress_bar(const implementation::builder_progress_bar& builder)
+	: styled_widget(builder, get_control_type())
+	, percentage_(static_cast<unsigned>(-1))
+{
+	// Force canvas update
+	set_percentage(0);
+}
+
 void progress_bar::set_active(const bool /*active*/)
 {
 	/* DO NOTHING */
@@ -146,9 +154,7 @@ builder_progress_bar::builder_progress_bar(const config& cfg)
 
 widget* builder_progress_bar::build() const
 {
-	progress_bar* widget = new progress_bar();
-
-	init_control(widget);
+	progress_bar* widget = new progress_bar(*this);
 
 	DBG_GUI_G << "Window builder: placed progress bar '" << id
 			  << "' with definition '" << definition << "'.\n";
diff --git a/src/gui/widgets/progress_bar.hpp b/src/gui/widgets/progress_bar.hpp
index 66c9639a99a9..c7d5453d7c0d 100644
--- a/src/gui/widgets/progress_bar.hpp
+++ b/src/gui/widgets/progress_bar.hpp
@@ -21,17 +21,17 @@
 
 namespace gui2
 {
+namespace implementation
+{
+struct builder_progress_bar;
+}
 
 // ------------ WIDGET -----------{
 
 class progress_bar : public styled_widget
 {
 public:
-	progress_bar() : styled_widget(), percentage_(static_cast<unsigned>(-1))
-	{
-		// Force canvas update
-		set_percentage(0);
-	}
+	explicit progress_bar(const implementation::builder_progress_bar& builder);
 
 	/***** ***** ***** ***** Inherited ***** ***** ***** *****/
 
diff --git a/src/gui/widgets/repeating_button.cpp b/src/gui/widgets/repeating_button.cpp
index 4a473c0e8aa4..b68069cddc2f 100644
--- a/src/gui/widgets/repeating_button.cpp
+++ b/src/gui/widgets/repeating_button.cpp
@@ -35,8 +35,11 @@ namespace gui2
 
 REGISTER_WIDGET(repeating_button)
 
-repeating_button::repeating_button()
-	: styled_widget(), clickable_item(), state_(ENABLED), repeat_timer_(0)
+repeating_button::repeating_button(const implementation::builder_repeating_button& builder)
+	: styled_widget(builder, get_control_type())
+	, clickable_item()
+	, state_(ENABLED)
+	, repeat_timer_(0)
 {
 	connect_signal<event::MOUSE_ENTER>(std::bind(
 			&repeating_button::signal_handler_mouse_enter, this, _2, _3));
@@ -249,9 +252,7 @@ builder_repeating_button::builder_repeating_button(const config& cfg)
 
 widget* builder_repeating_button::build() const
 {
-	repeating_button* widget = new repeating_button();
-
-	init_control(widget);
+	repeating_button* widget = new repeating_button(*this);
 
 	DBG_GUI_G << "Window builder: placed repeating button '" << id
 			  << "' with definition '" << definition << "'.\n";
diff --git a/src/gui/widgets/repeating_button.hpp b/src/gui/widgets/repeating_button.hpp
index 49bcab73200d..304bcdbcffce 100644
--- a/src/gui/widgets/repeating_button.hpp
+++ b/src/gui/widgets/repeating_button.hpp
@@ -22,13 +22,17 @@
 
 namespace gui2
 {
+namespace implementation
+{
+struct builder_repeating_button;
+}
 
 // ------------ WIDGET -----------{
 
 class repeating_button : public styled_widget, public clickable_item
 {
 public:
-	repeating_button();
+	explicit repeating_button(const implementation::builder_repeating_button& builder);
 	~repeating_button();
 
 	/**
diff --git a/src/gui/widgets/scroll_label.cpp b/src/gui/widgets/scroll_label.cpp
index 51c5bf4d15ef..1eed2b8d7754 100644
--- a/src/gui/widgets/scroll_label.cpp
+++ b/src/gui/widgets/scroll_label.cpp
@@ -39,11 +39,11 @@ namespace gui2
 
 REGISTER_WIDGET(scroll_label)
 
-scroll_label::scroll_label(bool wrap, const PangoAlignment text_alignment)
-	: scrollbar_container()
+scroll_label::scroll_label(const implementation::builder_scroll_label& builder)
+	: scrollbar_container(builder, get_control_type())
 	, state_(ENABLED)
-	, wrap_on_(wrap)
-	, text_alignment_(text_alignment)
+	, wrap_on_(builder.wrap_on)
+	, text_alignment_(builder.text_alignment)
 {
 	connect_signal<event::LEFT_BUTTON_DOWN>(
 		std::bind(&scroll_label::signal_handler_left_button_down, this, _2),
@@ -277,9 +277,7 @@ builder_scroll_label::builder_scroll_label(const config& cfg)
 
 widget* builder_scroll_label::build() const
 {
-	scroll_label* widget = new scroll_label(wrap_on, text_alignment);
-
-	init_control(widget);
+	scroll_label* widget = new scroll_label(*this);
 
 	widget->set_vertical_scrollbar_mode(vertical_scrollbar_mode);
 	widget->set_horizontal_scrollbar_mode(horizontal_scrollbar_mode);
diff --git a/src/gui/widgets/scroll_label.hpp b/src/gui/widgets/scroll_label.hpp
index e5253b5d18ca..a1d2bd1a0a89 100644
--- a/src/gui/widgets/scroll_label.hpp
+++ b/src/gui/widgets/scroll_label.hpp
@@ -44,7 +44,7 @@ class scroll_label : public scrollbar_container
 	friend struct implementation::builder_scroll_label;
 
 public:
-	scroll_label(bool wrap, const PangoAlignment text_alignment);
+	explicit scroll_label(const implementation::builder_scroll_label& builder);
 
 	/** See @ref styled_widget::set_label. */
 	virtual void set_label(const t_string& label) override;
diff --git a/src/gui/widgets/scrollbar.cpp b/src/gui/widgets/scrollbar.cpp
index 2e7ff0363640..5371dd583b4f 100644
--- a/src/gui/widgets/scrollbar.cpp
+++ b/src/gui/widgets/scrollbar.cpp
@@ -27,8 +27,8 @@
 namespace gui2
 {
 
-scrollbar_base::scrollbar_base()
-	: styled_widget()
+scrollbar_base::scrollbar_base(const implementation::builder_styled_widget& builder, const std::string& control_type)
+	: styled_widget(builder, control_type)
 	, state_(ENABLED)
 	, item_count_(0)
 	, item_position_(0)
@@ -51,6 +51,15 @@ scrollbar_base::scrollbar_base()
 			&scrollbar_base::signal_handler_left_button_up, this, _2, _3));
 }
 
+void scrollbar_base::finalize_setup()
+{
+	// These values won't change so set them once.
+	for(auto& tmp : get_canvases()) {
+		tmp.set_variable("offset_before", wfl::variant(offset_before()));
+		tmp.set_variable("offset_after", wfl::variant(offset_after()));
+	}
+}
+
 void scrollbar_base::scroll(const scroll_mode scroll)
 {
 	switch(scroll) {
@@ -148,7 +157,6 @@ void scrollbar_base::set_item_position(const unsigned item_position)
 
 void scrollbar_base::update_canvas()
 {
-
 	for(auto & tmp : get_canvases())
 	{
 		tmp.set_variable("positioner_offset", wfl::variant(positioner_offset_));
@@ -168,7 +176,7 @@ void scrollbar_base::set_state(const state_t state)
 void scrollbar_base::recalculate()
 {
 	// We can be called before the size has been set up in that case we can't do
-	// the proper recalcultion so stop before we die with an assert.
+	// the proper recalculation so stop before we die with an assert.
 	if(!get_length()) {
 		return;
 	}
@@ -303,16 +311,6 @@ void scrollbar_base::move_positioner(const int distance)
 	update_canvas();
 }
 
-void scrollbar_base::load_config_extra()
-{
-	// These values won't change so set them here.
-	for(auto & tmp : get_canvases())
-	{
-		tmp.set_variable("offset_before", wfl::variant(offset_before()));
-		tmp.set_variable("offset_after", wfl::variant(offset_after()));
-	}
-}
-
 void scrollbar_base::signal_handler_mouse_enter(const event::ui_event event,
 											 bool& handled,
 											 bool& halt)
diff --git a/src/gui/widgets/scrollbar.hpp b/src/gui/widgets/scrollbar.hpp
index c834de86f4a8..aa0c62bc3252 100644
--- a/src/gui/widgets/scrollbar.hpp
+++ b/src/gui/widgets/scrollbar.hpp
@@ -43,7 +43,7 @@ class scrollbar_base : public styled_widget
 	friend class slider;
 
 public:
-	scrollbar_base();
+	scrollbar_base(const implementation::builder_styled_widget& builder, const std::string& control_type);
 
 	/**
 	 * scroll 'step size'.
@@ -56,7 +56,7 @@ class scrollbar_base : public styled_widget
 		ITEM_BACKWARDS,		 /**< Go one item towards the begin. */
 		HALF_JUMP_BACKWARDS, /**< Go half the visible items towards the begin.
 								*/
-		JUMP_BACKWARDS,	/**< Go the visibile items towards the begin. */
+		JUMP_BACKWARDS,	/**< Go the visible items towards the begin. */
 		END,			   /**< Go to the end position. */
 		ITEM_FORWARD,	  /**< Go one item towards the end. */
 		HALF_JUMP_FORWARD, /**< Go half the visible items towards the end. */
@@ -148,6 +148,7 @@ class scrollbar_base : public styled_widget
 	{
 		return visible_items_;
 	}
+
 	void set_visible_items(const unsigned visible_items)
 	{
 		visible_items_ = visible_items;
@@ -158,6 +159,7 @@ class scrollbar_base : public styled_widget
 	{
 		return step_size_;
 	}
+
 	void set_step_size(const unsigned step_size)
 	{
 		step_size_ = step_size;
@@ -170,6 +172,8 @@ class scrollbar_base : public styled_widget
 	}
 
 protected:
+	void finalize_setup();
+
 	unsigned get_positioner_offset() const
 	{
 		return positioner_offset_;
@@ -356,9 +360,6 @@ class scrollbar_base : public styled_widget
 	*/
 	virtual void move_positioner(const int distance);
 
-	/** Inherited from styled_widget. */
-	void load_config_extra() override;
-
 	/***** ***** ***** signal handlers ***** ****** *****/
 
 	void signal_handler_mouse_enter(const event::ui_event event,
diff --git a/src/gui/widgets/scrollbar_container.cpp b/src/gui/widgets/scrollbar_container.cpp
index 4dfa78318706..36d864404846 100644
--- a/src/gui/widgets/scrollbar_container.cpp
+++ b/src/gui/widgets/scrollbar_container.cpp
@@ -66,8 +66,9 @@ const std::map<std::string, scrollbar_base::scroll_mode>& scroll_lookup()
 
 } // namespace
 
-scrollbar_container::scrollbar_container()
-	: container_base()
+scrollbar_container::scrollbar_container(const implementation::builder_styled_widget& builder,
+		const std::string& control_type)
+	: container_base(builder, control_type)
 	, state_(ENABLED)
 	, vertical_scrollbar_mode_(AUTO_VISIBLE_FIRST_RUN)
 	, horizontal_scrollbar_mode_(AUTO_VISIBLE_FIRST_RUN)
@@ -825,8 +826,7 @@ void scrollbar_container::finalize_setup()
 	}
 
 	/***** Setup the content *****/
-	content_ = new spacer();
-	content_->set_definition("default");
+	content_ = build_single_widget_instance<spacer>("spacer");
 
 	content_grid_ = dynamic_cast<grid*>(
 			get_grid().swap_child("_content_grid", content_, true).release());
diff --git a/src/gui/widgets/scrollbar_container.hpp b/src/gui/widgets/scrollbar_container.hpp
index f72b2c4edd82..98c162dadc33 100644
--- a/src/gui/widgets/scrollbar_container.hpp
+++ b/src/gui/widgets/scrollbar_container.hpp
@@ -27,6 +27,7 @@ namespace implementation
 {
 struct builder_scroll_label;
 struct builder_scrollbar_panel;
+struct builder_styled_widget;
 }
 
 /**
@@ -50,7 +51,8 @@ class scrollbar_container : public container_base
 	friend struct scrollbar_container_implementation;
 
 public:
-	scrollbar_container();
+	explicit scrollbar_container(const implementation::builder_styled_widget& builder,
+		const std::string& control_type);
 
 	~scrollbar_container()
 	{
diff --git a/src/gui/widgets/scrollbar_panel.cpp b/src/gui/widgets/scrollbar_panel.cpp
index 9050eff0e3fd..582778947b3e 100644
--- a/src/gui/widgets/scrollbar_panel.cpp
+++ b/src/gui/widgets/scrollbar_panel.cpp
@@ -32,6 +32,11 @@ namespace gui2
 
 REGISTER_WIDGET(scrollbar_panel)
 
+scrollbar_panel::scrollbar_panel(const implementation::builder_scrollbar_panel& builder)
+	: scrollbar_container(builder, get_control_type())
+{
+}
+
 bool scrollbar_panel::get_active() const
 {
 	return true;
@@ -152,9 +157,7 @@ builder_scrollbar_panel::builder_scrollbar_panel(const config& cfg)
 
 widget* builder_scrollbar_panel::build() const
 {
-	scrollbar_panel* panel = new scrollbar_panel();
-
-	init_control(panel);
+	scrollbar_panel* panel = new scrollbar_panel(*this);
 
 	panel->set_vertical_scrollbar_mode(vertical_scrollbar_mode);
 	panel->set_horizontal_scrollbar_mode(horizontal_scrollbar_mode);
diff --git a/src/gui/widgets/scrollbar_panel.hpp b/src/gui/widgets/scrollbar_panel.hpp
index 361c0cea3789..600c93b78e42 100644
--- a/src/gui/widgets/scrollbar_panel.hpp
+++ b/src/gui/widgets/scrollbar_panel.hpp
@@ -43,10 +43,7 @@ class scrollbar_panel : public scrollbar_container
 	/**
 	 * Constructor.
 	 */
-	scrollbar_panel()
-		: scrollbar_container()
-	{
-	}
+	explicit scrollbar_panel(const implementation::builder_scrollbar_panel& builder);
 
 	/** See @ref styled_widget::get_active. */
 	virtual bool get_active() const override;
diff --git a/src/gui/widgets/size_lock.cpp b/src/gui/widgets/size_lock.cpp
index 858ea571da63..45f1c04883a3 100644
--- a/src/gui/widgets/size_lock.cpp
+++ b/src/gui/widgets/size_lock.cpp
@@ -27,6 +27,12 @@ namespace gui2
 
 REGISTER_WIDGET(size_lock)
 
+size_lock::size_lock(const implementation::builder_size_lock& builder)
+	: container_base(builder, get_control_type())
+	, widget_(nullptr)
+{
+}
+
 void size_lock::place(const point& origin, const point& size)
 {
 	point content_size = widget_->get_best_size();
@@ -137,9 +143,7 @@ builder_size_lock::builder_size_lock(const config& cfg) :
 
 widget* builder_size_lock::build() const
 {
-	size_lock* widget = new size_lock();
-
-	init_control(widget);
+	size_lock* widget = new size_lock(*this);
 
 	DBG_GUI_G << "Window builder: placed fixed size widget '" << id <<
 		"' with definition '" << definition << "'.\n";
diff --git a/src/gui/widgets/size_lock.hpp b/src/gui/widgets/size_lock.hpp
index 67cb0dda1cb5..e5e663879f8f 100644
--- a/src/gui/widgets/size_lock.hpp
+++ b/src/gui/widgets/size_lock.hpp
@@ -36,10 +36,7 @@ class size_lock : public container_base
 	friend struct implementation::builder_size_lock;
 
 public:
-	size_lock() :
-		container_base(),
-		widget_(nullptr)
-	{}
+	explicit size_lock(const implementation::builder_size_lock& builder);
 
 	/** See @ref control::get_active. */
 	bool get_active() const override
diff --git a/src/gui/widgets/slider.cpp b/src/gui/widgets/slider.cpp
index 49375bd9d6a2..fece4862aaa0 100644
--- a/src/gui/widgets/slider.cpp
+++ b/src/gui/widgets/slider.cpp
@@ -37,8 +37,8 @@ namespace gui2
 
 REGISTER_WIDGET(slider)
 
-slider::slider()
-	: scrollbar_base()
+slider::slider(const implementation::builder_slider& builder)
+	: scrollbar_base(builder, get_control_type())
 	, best_slider_length_(0)
 	, minimum_value_(0)
 	, minimum_value_label_()
@@ -487,15 +487,15 @@ builder_slider::builder_slider(const config& cfg)
 
 widget* builder_slider::build() const
 {
-	slider* widget = new slider();
-
-	init_control(widget);
+	slider* widget = new slider(*this);
 
 	widget->set_best_slider_length(best_slider_length_);
 	widget->set_maximum_value(maximum_value_);
 	widget->set_minimum_value(minimum_value_);
 	widget->set_step_size(step_size_);
 	widget->set_value(value_);
+	
+	widget->finalize_setup();
 
 	if(!value_labels_.empty()) {
 		VALIDATE(value_labels_.size() == widget->get_item_count(),
diff --git a/src/gui/widgets/slider.hpp b/src/gui/widgets/slider.hpp
index ce76e72db097..553f4d5ca4b0 100644
--- a/src/gui/widgets/slider.hpp
+++ b/src/gui/widgets/slider.hpp
@@ -22,14 +22,20 @@
 
 namespace gui2
 {
+namespace implementation
+{
+struct builder_slider;
+}
 
 // ------------ WIDGET -----------{
 
 /** A slider. */
 class slider : public scrollbar_base, public integer_selector
 {
+	friend struct implementation::builder_slider;
+
 public:
-	slider();
+	explicit slider(const implementation::builder_slider& builder);
 
 	/***** ***** ***** ***** layout functions ***** ***** ***** *****/
 
@@ -178,8 +184,8 @@ class slider : public scrollbar_base, public integer_selector
 	tlabel_creator value_labels_;
 
 	/**
-	 * When initially pessing the positioner and every time a new value is chosen through dragging,
-	 * this value is upda with the mouse position at the time. This allows the widget to track
+	 * When initially pressing the positioner and every time a new value is chosen through dragging,
+	 * this value is updated with the mouse position at the time. This allows the widget to track
 	 * how far the mouse has moved since setting the last value.
 	 */
 	point current_item_mouse_position_;
diff --git a/src/gui/widgets/spacer.cpp b/src/gui/widgets/spacer.cpp
index 788b9ba3abda..5cb8dbd649ac 100644
--- a/src/gui/widgets/spacer.cpp
+++ b/src/gui/widgets/spacer.cpp
@@ -28,6 +28,13 @@ namespace gui2
 
 REGISTER_WIDGET(spacer)
 
+spacer::spacer(const implementation::builder_spacer& builder, const std::string& w, const std::string& h)
+	: styled_widget(builder, get_control_type())
+	, width_(w)
+	, height_(h)
+{
+}
+
 bool spacer::fills_available_space()
 {
 	return (!width_.has_formula() && width_() == 0) && (!height_.has_formula() && height_() == 0);
@@ -178,9 +185,7 @@ builder_spacer::builder_spacer(const config& cfg)
 
 widget* builder_spacer::build() const
 {
-	spacer* widget = new spacer(width_, height_);
-
-	init_control(widget);
+	spacer* widget = new spacer(*this, width_, height_);
 
 	DBG_GUI_G << "Window builder: placed spacer '" << id
 			  << "' with definition '" << definition << "'.\n";
diff --git a/src/gui/widgets/spacer.hpp b/src/gui/widgets/spacer.hpp
index 4039a4de0659..792a8659b44f 100644
--- a/src/gui/widgets/spacer.hpp
+++ b/src/gui/widgets/spacer.hpp
@@ -22,6 +22,10 @@
 
 namespace gui2
 {
+namespace implementation
+{
+struct builder_spacer;
+}
 
 // ------------ WIDGET -----------{
 
@@ -37,12 +41,7 @@ namespace gui2
 class spacer : public styled_widget
 {
 public:
-	spacer(const std::string& w = "0", const std::string& h = "0")
-		: styled_widget()
-		, width_(w)
-		, height_(h)
-	{
-	}
+	spacer(const implementation::builder_spacer& builder, const std::string& w = "0", const std::string& h = "0");
 
 	/***** ***** ***** ***** layout functions ***** ***** ***** *****/
 
diff --git a/src/gui/widgets/stacked_widget.cpp b/src/gui/widgets/stacked_widget.cpp
index 32f9d9dc6e84..1df890fc1f3b 100644
--- a/src/gui/widgets/stacked_widget.cpp
+++ b/src/gui/widgets/stacked_widget.cpp
@@ -33,8 +33,8 @@ namespace gui2
 
 REGISTER_WIDGET(stacked_widget)
 
-stacked_widget::stacked_widget()
-	: container_base()
+stacked_widget::stacked_widget(const implementation::builder_stacked_widget& builder)
+	: container_base(builder, get_control_type())
 	, generator_(generator_base::build(false, false, generator_base::independent, false))
 	, selected_layer_(-1)
 {
@@ -250,9 +250,7 @@ builder_stacked_widget::builder_stacked_widget(const config& real_cfg)
 
 widget* builder_stacked_widget::build() const
 {
-	stacked_widget* widget = new stacked_widget();
-
-	init_control(widget);
+	stacked_widget* widget = new stacked_widget(*this);
 
 	DBG_GUI_G << "Window builder: placed stacked widget '" << id
 			  << "' with definition '" << definition << "'.\n";
diff --git a/src/gui/widgets/stacked_widget.hpp b/src/gui/widgets/stacked_widget.hpp
index c56f21da7070..ca12fccac096 100644
--- a/src/gui/widgets/stacked_widget.hpp
+++ b/src/gui/widgets/stacked_widget.hpp
@@ -39,7 +39,7 @@ class stacked_widget : public container_base
 	friend class debug_layout_graph;
 
 public:
-	stacked_widget();
+	explicit stacked_widget(const implementation::builder_stacked_widget& builder);
 
 	/***** ***** ***** inherited ***** ****** *****/
 
diff --git a/src/gui/widgets/styled_widget.cpp b/src/gui/widgets/styled_widget.cpp
index e667cce2de9c..68b884084357 100644
--- a/src/gui/widgets/styled_widget.cpp
+++ b/src/gui/widgets/styled_widget.cpp
@@ -43,31 +43,6 @@ namespace gui2
 
 // ------------ WIDGET -----------{
 
-styled_widget::styled_widget()
-	: definition_("default")
-	, label_()
-	, use_markup_(false)
-	, use_tooltip_on_label_overflow_(true)
-	, tooltip_()
-	, help_message_()
-	, canvas_()
-	, config_(nullptr)
-	, renderer_()
-	, text_maximum_width_(0)
-	, text_alignment_(PANGO_ALIGN_LEFT)
-	, text_ellipse_mode_(PANGO_ELLIPSIZE_END)
-	, shrunken_(false)
-{
-	connect_signal<event::SHOW_TOOLTIP>(std::bind(
-			&styled_widget::signal_handler_show_tooltip, this, _2, _3, _5));
-
-	connect_signal<event::SHOW_HELPTIP>(std::bind(
-			&styled_widget::signal_handler_show_helptip, this, _2, _3, _5));
-
-	connect_signal<event::NOTIFY_REMOVE_TOOLTIP>(std::bind(
-			&styled_widget::signal_handler_notify_remove_tooltip, this, _2, _3));
-}
-
 styled_widget::styled_widget(const implementation::builder_styled_widget& builder,
 				   const std::string& control_type)
 	: widget(builder)
@@ -296,16 +271,6 @@ void styled_widget::place(const point& origin, const point& size)
 	update_canvas();
 }
 
-void styled_widget::load_config()
-{
-	if(!config()) {
-
-		definition_load_configuration(get_control_type());
-
-		load_config_extra();
-	}
-}
-
 widget* styled_widget::find_at(const point& coordinate, const bool must_be_active)
 {
 	return (widget::find_at(coordinate, must_be_active)
@@ -340,16 +305,6 @@ const widget* styled_widget::find(const std::string& id, const bool must_be_acti
 				   : nullptr;
 }
 
-void styled_widget::set_definition(const std::string& definition)
-{
-	assert(!config());
-	definition_ = definition;
-	load_config();
-	assert(config());
-
-	init();
-}
-
 void styled_widget::set_label(const t_string& label)
 {
 	if(label == label_) {
@@ -406,9 +361,16 @@ void styled_widget::update_canvas()
 		canvas.set_variable("text", wfl::variant(label_));
 		canvas.set_variable("text_markup", wfl::variant(use_markup_));
 		canvas.set_variable("text_link_aware", wfl::variant(get_link_aware()));
-		// Possible TODO: Consider making a formula_callable for colours
+
+		// Possible TODO: consider making a formula_callable for colors.
 		color_t link_color = get_link_color();
-		std::vector<wfl::variant> link_color_as_list{wfl::variant(link_color.r), wfl::variant(link_color.g), wfl::variant(link_color.b), wfl::variant(link_color.a)};
+		std::vector<wfl::variant> link_color_as_list {
+			wfl::variant(link_color.r),
+			wfl::variant(link_color.g),
+			wfl::variant(link_color.b),
+			wfl::variant(link_color.a)
+		};
+
 		canvas.set_variable("text_link_color", wfl::variant(link_color_as_list));
 		canvas.set_variable("text_alignment",
 							wfl::variant(encode_text_alignment(text_alignment_)));
@@ -706,22 +668,6 @@ builder_styled_widget::builder_styled_widget(const config& cfg)
 			  << "' and definition '" << definition << "'.\n";
 }
 
-void builder_styled_widget::init_control(styled_widget* control) const
-{
-	assert(control);
-
-	control->set_id(id);
-	control->set_definition(definition);
-	control->set_linked_group(linked_group);
-	control->set_label(label_string);
-	control->set_tooltip(tooltip);
-	control->set_help_message(help);
-	control->set_use_tooltip_on_label_overflow(use_tooltip_on_label_overflow);
-	control->set_use_markup(use_markup);
-	control->set_debug_border_mode(debug_border_mode);
-	control->set_debug_border_color(debug_border_color);
-}
-
 widget* builder_styled_widget::build(const replacements_map& /*replacements*/) const
 {
 	return build();
diff --git a/src/gui/widgets/styled_widget.hpp b/src/gui/widgets/styled_widget.hpp
index 9b16728bb45f..4b6aacf5ff59 100644
--- a/src/gui/widgets/styled_widget.hpp
+++ b/src/gui/widgets/styled_widget.hpp
@@ -35,9 +35,6 @@ class styled_widget : public widget
 	friend class debug_layout_graph;
 
 public:
-	/** @deprecated Used the second overload. */
-	styled_widget();
-
 	/**
 	 * Constructor.
 	 *
@@ -186,18 +183,6 @@ class styled_widget : public widget
 	/***** ***** ***** ***** Inherited ***** ***** ***** *****/
 
 private:
-	/**
-	 * Loads the configuration of the widget.
-	 *
-	 * Controls have their definition stored in a definition object. In order to
-	 * determine sizes and drawing the widget this definition needs to be
-	 * loaded. The member definition_ contains the name of the definition and
-	 * function load the proper configuration.
-	 *
-	 * @deprecated @ref definition_load_configuration() is the replacement.
-	 */
-	void load_config();
-
 	/**
 	 * Uses the load function.
 	 *
@@ -223,17 +208,6 @@ class styled_widget : public widget
 	const widget* find(const std::string& id,
 						const bool must_be_active) const override;
 
-	/**
-	 * Sets the definition.
-	 *
-	 * This function sets the definition of a styled_widget and should be called soon
-	 * after creating the object since a lot of internal functions depend on the
-	 * definition.
-	 *
-	 * This function should be called one time only!!!
-	 */
-	void set_definition(const std::string& definition);
-
 	/***** ***** ***** setters / getters for members ***** ****** *****/
 	bool get_use_tooltip_on_label_overflow() const
 	{
@@ -249,9 +223,11 @@ class styled_widget : public widget
 	{
 		return label_;
 	}
+
 	virtual void set_label(const t_string& label);
 
 	virtual void set_use_markup(bool use_markup);
+
 	bool get_use_markup() const
 	{
 		return use_markup_;
@@ -293,6 +269,7 @@ class styled_widget : public widget
 	}
 
 	virtual void set_text_alignment(const PangoAlignment text_alignment);
+
 	PangoAlignment get_text_alignment() const
 	{
 		return text_alignment_;
@@ -334,7 +311,8 @@ class styled_widget : public widget
 	std::shared_ptr<const typename T::resolution> cast_config_to() const
 	{
 		static_assert(std::is_base_of<resolution_definition, typename T::resolution>::value,
-			"Given type's resolution object does not derive from resolution_definition.");
+			"Given type's resolution object does not derive from resolution_definition."
+		);
 
 		return std::static_pointer_cast<const typename T::resolution>(config());
 	}
@@ -430,16 +408,6 @@ class styled_widget : public widget
 	 */
 	resolution_definition_ptr config_;
 
-	/**
-	 * Load class dependent config settings.
-	 *
-	 * load_config will call this method after loading the config, by default it
-	 * does nothing but classes can override it to implement custom behavior.
-	 */
-	virtual void load_config_extra()
-	{
-	}
-
 	/**
 	 * Loads the configuration of the widget.
 	 *
@@ -479,19 +447,6 @@ class styled_widget : public widget
 	std::string get_label_link(const gui2::point & position) const;
 
 private:
-	/**
-	 * Allows derived classes to implement initialization steps after the config and
-	 * canvases have been loaded.
-	 *
-	 * Another area this is useful is for initialization making use of virtual functions,
-	 * which can't be used in a constructor.
-	 *
-	 * This function should only be called once.
-	 */
-	virtual void init()
-	{
-	}
-
 	/**
 	 * Gets the best size for a text.
 	 *
@@ -568,9 +523,6 @@ struct builder_styled_widget : public builder_widget
 
 	virtual widget* build(const replacements_map& replacements) const override;
 
-	/** @deprecated The styled_widget can initialize itself. */
-	void init_control(styled_widget* styled_widget) const;
-
 	/** Parameters for the styled_widget. */
 	std::string definition;
 	t_string label_string;
diff --git a/src/gui/widgets/text_box.cpp b/src/gui/widgets/text_box.cpp
index 310b563328cc..42369d59e773 100644
--- a/src/gui/widgets/text_box.cpp
+++ b/src/gui/widgets/text_box.cpp
@@ -95,8 +95,8 @@ std::string text_history::get_value() const
 	}
 }
 
-text_box::text_box()
-	: text_box_base()
+text_box::text_box(const implementation::builder_styled_widget& builder)
+	: text_box_base(builder, get_control_type())
 	, history_()
 	, max_input_length_(0)
 	, text_x_offset_(0)
@@ -114,6 +114,8 @@ text_box::text_box()
 			&text_box::signal_handler_left_button_up, this, _2, _3));
 	connect_signal<event::LEFT_BUTTON_DOUBLE_CLICK>(std::bind(
 			&text_box::signal_handler_left_button_double_click, this, _2, _3));
+
+	update_offsets();
 }
 
 void text_box::place(const point& origin, const point& size)
@@ -333,19 +335,6 @@ void text_box::handle_key_clear_line(SDL_Keymod /*modifier*/, bool& handled)
 	set_value("");
 }
 
-void text_box::load_config_extra()
-{
-	assert(config());
-
-	const auto conf = cast_config_to<text_box_definition>();
-	assert(conf);
-
-	set_font_size(conf->text_font_size);
-	set_font_style(conf->text_font_style);
-
-	update_offsets();
-}
-
 const std::string& text_box::get_control_type() const
 {
 	static const std::string type = "text_box";
@@ -494,9 +483,7 @@ builder_text_box::builder_text_box(const config& cfg)
 
 widget* builder_text_box::build() const
 {
-	text_box* widget = new text_box();
-
-	init_control(widget);
+	text_box* widget = new text_box(*this);
 
 	// A textbox doesn't have a label but a text
 	widget->set_value(label_string);
@@ -507,6 +494,12 @@ widget* builder_text_box::build() const
 
 	widget->set_max_input_length(max_input_length);
 
+	const auto conf = widget->cast_config_to<text_box_definition>();
+	assert(conf);
+
+	widget->set_font_size(conf->text_font_size);
+	widget->set_font_style(conf->text_font_style);
+
 	DBG_GUI_G << "Window builder: placed text box '" << id
 			  << "' with definition '" << definition << "'.\n";
 
diff --git a/src/gui/widgets/text_box.hpp b/src/gui/widgets/text_box.hpp
index 390c3967a202..1b1789ed8b00 100644
--- a/src/gui/widgets/text_box.hpp
+++ b/src/gui/widgets/text_box.hpp
@@ -18,6 +18,10 @@
 
 namespace gui2
 {
+namespace implementation
+{
+struct builder_text_box;
+}
 
 // ------------ WIDGET -----------{
 
@@ -116,8 +120,10 @@ class text_history
 /** Class for a single line text area. */
 class text_box : public text_box_base
 {
+	friend struct implementation::builder_text_box;
+
 public:
-	text_box();
+	explicit text_box(const implementation::builder_styled_widget& builder);
 
 	/** Saves the text in the widget to the history. */
 	void save_to_history()
@@ -255,9 +261,6 @@ class text_box : public text_box_base
 	/** See @ref styled_widget::get_control_type. */
 	virtual const std::string& get_control_type() const override;
 
-	/** Inherited from styled_widget. */
-	void load_config_extra() override;
-
 	/***** ***** ***** signal handlers ***** ****** *****/
 
 	void signal_handler_mouse_motion(const event::ui_event event,
diff --git a/src/gui/widgets/text_box_base.cpp b/src/gui/widgets/text_box_base.cpp
index 487caf7e64e1..bd96a0729477 100644
--- a/src/gui/widgets/text_box_base.cpp
+++ b/src/gui/widgets/text_box_base.cpp
@@ -32,8 +32,8 @@
 namespace gui2
 {
 
-text_box_base::text_box_base()
-	: styled_widget()
+text_box_base::text_box_base(const implementation::builder_styled_widget& builder, const std::string& control_type)
+	: styled_widget(builder, control_type)
 	, state_(ENABLED)
 	, text_()
 	, selection_start_(0)
diff --git a/src/gui/widgets/text_box_base.hpp b/src/gui/widgets/text_box_base.hpp
index d0247c39bd8e..7cbe9b08c95c 100644
--- a/src/gui/widgets/text_box_base.hpp
+++ b/src/gui/widgets/text_box_base.hpp
@@ -24,6 +24,10 @@
 
 namespace gui2
 {
+namespace implementation
+{
+	struct builder_styled_widget;
+}
 
 /**
  * Abstract base class for text items.
@@ -43,7 +47,7 @@ class text_box_base : public styled_widget
 {
 
 public:
-	text_box_base();
+	text_box_base(const implementation::builder_styled_widget& builder, const std::string& control_type);
 
 	~text_box_base();
 
diff --git a/src/gui/widgets/toggle_button.cpp b/src/gui/widgets/toggle_button.cpp
index b5e57c556c5e..40b7039dba5e 100644
--- a/src/gui/widgets/toggle_button.cpp
+++ b/src/gui/widgets/toggle_button.cpp
@@ -36,8 +36,8 @@ namespace gui2
 
 REGISTER_WIDGET(toggle_button)
 
-toggle_button::toggle_button()
-	: styled_widget()
+toggle_button::toggle_button(const implementation::builder_toggle_button& builder)
+	: styled_widget(builder, get_control_type())
 	, state_(ENABLED)
 	, state_num_(0)
 	, retval_(0)
@@ -290,9 +290,7 @@ builder_toggle_button::builder_toggle_button(const config& cfg)
 
 widget* builder_toggle_button::build() const
 {
-	toggle_button* widget = new toggle_button();
-
-	init_control(widget);
+	toggle_button* widget = new toggle_button(*this);
 
 	widget->set_icon_name(icon_name_);
 	widget->set_retval(get_retval(retval_id_, retval_, id));
diff --git a/src/gui/widgets/toggle_button.hpp b/src/gui/widgets/toggle_button.hpp
index 2200d4f65a57..bae322579845 100644
--- a/src/gui/widgets/toggle_button.hpp
+++ b/src/gui/widgets/toggle_button.hpp
@@ -19,6 +19,10 @@
 
 namespace gui2
 {
+namespace implementation
+{	
+	struct builder_toggle_button;
+}
 
 // ------------ WIDGET -----------{
 
@@ -31,7 +35,7 @@ namespace gui2
 class toggle_button : public styled_widget, public selectable_item
 {
 public:
-	toggle_button();
+	explicit toggle_button(const implementation::builder_toggle_button& builder);
 
 	/***** ***** ***** ***** Inherited ***** ***** ***** *****/
 
diff --git a/src/gui/widgets/toggle_panel.cpp b/src/gui/widgets/toggle_panel.cpp
index 62fe488bd571..1606b5dbba5e 100644
--- a/src/gui/widgets/toggle_panel.cpp
+++ b/src/gui/widgets/toggle_panel.cpp
@@ -37,8 +37,8 @@ namespace gui2
 
 REGISTER_WIDGET(toggle_panel)
 
-toggle_panel::toggle_panel()
-	: panel()
+toggle_panel::toggle_panel(const implementation::builder_toggle_panel& builder)
+	: panel(builder, get_control_type())
 	, state_(ENABLED)
 	, state_num_(0)
 	, retval_(0)
@@ -419,9 +419,7 @@ builder_toggle_panel::builder_toggle_panel(const config& cfg)
 
 widget* builder_toggle_panel::build() const
 {
-	toggle_panel* widget = new toggle_panel();
-
-	init_control(widget);
+	toggle_panel* widget = new toggle_panel(*this);
 
 	widget->set_retval(get_retval(retval_id_, retval_, id));
 
diff --git a/src/gui/widgets/toggle_panel.hpp b/src/gui/widgets/toggle_panel.hpp
index 6c1ea60078ba..468a9fde1679 100644
--- a/src/gui/widgets/toggle_panel.hpp
+++ b/src/gui/widgets/toggle_panel.hpp
@@ -20,6 +20,11 @@
 namespace gui2
 {
 
+namespace implementation
+{
+struct builder_toggle_panel;
+}
+
 // ------------ WIDGET -----------{
 
 /**
@@ -33,7 +38,7 @@ namespace gui2
 class toggle_panel : public panel, public selectable_item
 {
 public:
-	toggle_panel();
+	explicit toggle_panel(const implementation::builder_toggle_panel& builder);
 
 	/**
 	 * Sets the members of the child controls.
diff --git a/src/gui/widgets/tree_view.cpp b/src/gui/widgets/tree_view.cpp
index eb6a4db78c28..3b1abd417c74 100644
--- a/src/gui/widgets/tree_view.cpp
+++ b/src/gui/widgets/tree_view.cpp
@@ -37,9 +37,9 @@ namespace gui2
 
 REGISTER_WIDGET(tree_view)
 
-tree_view::tree_view(const std::vector<node_definition>& node_definitions)
-	: scrollbar_container()
-	, node_definitions_(node_definitions)
+tree_view::tree_view(const implementation::builder_tree_view& builder)
+	: scrollbar_container(builder, get_control_type())
+	, node_definitions_(builder.nodes)
 	, indentation_step_size_(0)
 	, need_layout_(false)
 	, root_node_(new tree_view_node("root",
@@ -398,9 +398,7 @@ widget* builder_tree_view::build() const
 	 *  TODO see how much we can move in the constructor instead of
 	 *  building in several steps.
 	 */
-	tree_view* widget = new tree_view(nodes);
-
-	init_control(widget);
+	tree_view* widget = new tree_view(*this);
 
 	widget->set_vertical_scrollbar_mode(vertical_scrollbar_mode);
 	widget->set_horizontal_scrollbar_mode(horizontal_scrollbar_mode);
diff --git a/src/gui/widgets/tree_view.hpp b/src/gui/widgets/tree_view.hpp
index abd0035d47ca..9b7170b38c32 100644
--- a/src/gui/widgets/tree_view.hpp
+++ b/src/gui/widgets/tree_view.hpp
@@ -43,7 +43,7 @@ class tree_view : public scrollbar_container
 public:
 	typedef implementation::tree_node node_definition;
 
-	explicit tree_view(const std::vector<node_definition>& node_definitions);
+	explicit tree_view(const implementation::builder_tree_view& builder);
 
 	~tree_view();
 
diff --git a/src/gui/widgets/unit_preview_pane.cpp b/src/gui/widgets/unit_preview_pane.cpp
index 8da25ad09768..cc5d7eaef5f7 100644
--- a/src/gui/widgets/unit_preview_pane.cpp
+++ b/src/gui/widgets/unit_preview_pane.cpp
@@ -62,6 +62,22 @@ namespace gui2
 
 REGISTER_WIDGET(unit_preview_pane)
 
+unit_preview_pane::unit_preview_pane(const implementation::builder_unit_preview_pane& builder)
+	: container_base(builder, get_control_type())
+	, current_type_()
+	, icon_type_(nullptr)
+	, icon_race_(nullptr)
+	, icon_alignment_(nullptr)
+	, label_name_(nullptr)
+	, label_level_(nullptr)
+	, label_race_(nullptr)
+	, label_details_(nullptr)
+	, tree_details_(nullptr)
+	, button_profile_(nullptr)
+	, image_mods_()
+{
+}
+
 void unit_preview_pane::finalize_setup()
 {
 	// Icons
@@ -588,9 +604,7 @@ builder_unit_preview_pane::builder_unit_preview_pane(const config& cfg)
 
 widget* builder_unit_preview_pane::build() const
 {
-	unit_preview_pane* widget = new unit_preview_pane();
-
-	init_control(widget);
+	unit_preview_pane* widget = new unit_preview_pane(*this);
 
 	DBG_GUI_G << "Window builder: placed unit preview pane '" << id
 			  << "' with definition '" << definition << "'.\n";
diff --git a/src/gui/widgets/unit_preview_pane.hpp b/src/gui/widgets/unit_preview_pane.hpp
index 86f59793c8db..4ae972f95670 100644
--- a/src/gui/widgets/unit_preview_pane.hpp
+++ b/src/gui/widgets/unit_preview_pane.hpp
@@ -41,21 +41,7 @@ class unit_preview_pane : public container_base
 	friend struct implementation::builder_unit_preview_pane;
 
 public:
-	unit_preview_pane()
-		: container_base()
-		, current_type_()
-		, icon_type_(nullptr)
-		, icon_race_(nullptr)
-		, icon_alignment_(nullptr)
-		, label_name_(nullptr)
-		, label_level_(nullptr)
-		, label_race_(nullptr)
-		, label_details_(nullptr)
-		, tree_details_(nullptr)
-		, button_profile_(nullptr)
-		, image_mods_()
-	{
-	}
+	explicit unit_preview_pane(const implementation::builder_unit_preview_pane& builder);
 
 	/** Displays the stats of a specified unit type */
 	void set_displayed_type(const unit_type& type);
diff --git a/src/gui/widgets/vertical_scrollbar.cpp b/src/gui/widgets/vertical_scrollbar.cpp
index 671ce6b0b54d..f18fa1c959ad 100644
--- a/src/gui/widgets/vertical_scrollbar.cpp
+++ b/src/gui/widgets/vertical_scrollbar.cpp
@@ -28,6 +28,11 @@ namespace gui2
 
 REGISTER_WIDGET(vertical_scrollbar)
 
+vertical_scrollbar::vertical_scrollbar(const implementation::builder_vertical_scrollbar& builder)
+	: scrollbar_base(builder, get_control_type())
+{
+}
+
 unsigned vertical_scrollbar::minimum_positioner_length() const
 {
 	const auto conf = cast_config_to<vertical_scrollbar_definition>();
@@ -197,9 +202,9 @@ builder_vertical_scrollbar::builder_vertical_scrollbar(const config& cfg)
 
 widget* builder_vertical_scrollbar::build() const
 {
-	vertical_scrollbar* widget = new vertical_scrollbar();
+	vertical_scrollbar* widget = new vertical_scrollbar(*this);
 
-	init_control(widget);
+	widget->finalize_setup();
 
 	DBG_GUI_G << "Window builder:"
 			  << " placed vertical scrollbar '" << id << "' with definition '"
diff --git a/src/gui/widgets/vertical_scrollbar.hpp b/src/gui/widgets/vertical_scrollbar.hpp
index efd1ca2eeafc..521d36dfc8fe 100644
--- a/src/gui/widgets/vertical_scrollbar.hpp
+++ b/src/gui/widgets/vertical_scrollbar.hpp
@@ -18,16 +18,20 @@
 
 namespace gui2
 {
+namespace implementation
+{
+struct builder_vertical_scrollbar;
+}
 
 // ------------ WIDGET -----------{
 
 /** A vertical scrollbar. */
 class vertical_scrollbar : public scrollbar_base
 {
+	friend struct implementation::builder_vertical_scrollbar;
+
 public:
-	vertical_scrollbar() : scrollbar_base()
-	{
-	}
+	explicit vertical_scrollbar(const implementation::builder_vertical_scrollbar& builder);
 
 private:
 	/** Inherited from tscrollbar. */
diff --git a/src/gui/widgets/window.cpp b/src/gui/widgets/window.cpp
index 76c92da93ca7..ba222467b5df 100644
--- a/src/gui/widgets/window.cpp
+++ b/src/gui/widgets/window.cpp
@@ -304,7 +304,7 @@ window::window(CVideo& video,
 				 const std::string& definition,
 				 const builder_window::window_resolution::tooltip_info& tooltip,
 				 const builder_window::window_resolution::tooltip_info& helptip)
-	: panel()
+	: panel(implementation::builder_window(::config {"definition", definition->definition}), get_control_type())
 	, cursor::setter(cursor::NORMAL)
 	, video_(video)
 	, status_(NEW)
@@ -344,11 +344,6 @@ window::window(CVideo& video,
 	, exit_hook_([](window&)->bool { return true; })
 	, callback_next_draw_(nullptr)
 {
-	// We load the config in here as exception.
-	// Our caller did update the screen size so no need for us to do that again.
-	set_definition(definition);
-	load_config();
-
 	manager::instance().add(*this);
 
 	connect();