25 files changed, 213 insertions, 91 deletions

diff --git a/core/config/project_settings.cpp b/core/config/project_settings.cpp
index cbbfe3de75..93934f2320 100644
--- a/core/config/project_settings.cpp
+++ b/core/config/project_settings.cpp
@@ -852,8 +852,8 @@ Error ProjectSettings::_save_settings_binary(const String &p_file, const RBMap<S
 	}
 
 	if (!p_custom_features.is_empty()) {
+		// Store how many properties are saved, add one for custom features, which must always go first.
 		file->store_32(count + 1);
-		//store how many properties are saved, add one for custom featuers, which must always go first
 		String key = CoreStringNames::get_singleton()->_custom_features;
 		file->store_pascal_string(key);
 
@@ -870,7 +870,8 @@ Error ProjectSettings::_save_settings_binary(const String &p_file, const RBMap<S
 		file->store_buffer(buff.ptr(), buff.size());
 
 	} else {
-		file->store_32(count); //store how many properties are saved
+		// Store how many properties are saved.
+		file->store_32(count);
 	}
 
 	for (const KeyValue<String, List<String>> &E : p_props) {
diff --git a/core/extension/gdextension.cpp b/core/extension/gdextension.cpp
index 6c3d0a6148..2bac1f6592 100644
--- a/core/extension/gdextension.cpp
+++ b/core/extension/gdextension.cpp
@@ -678,12 +678,11 @@ GDExtensionInterfaceFunctionPtr GDExtension::get_interface_function(StringName p
 }
 
 Error GDExtension::open_library(const String &p_path, const String &p_entry_symbol) {
-	library_path = p_path;
-
 	String abs_path = ProjectSettings::get_singleton()->globalize_path(p_path);
 #if defined(WINDOWS_ENABLED) && defined(TOOLS_ENABLED)
 	// If running on the editor on Windows, we copy the library and open the copy.
 	// This is so the original file isn't locked and can be updated by a compiler.
+	bool library_copied = false;
 	if (Engine::get_singleton()->is_editor_hint()) {
 		if (!FileAccess::exists(abs_path)) {
 			ERR_PRINT("GDExtension library not found: " + library_path);
@@ -705,6 +704,7 @@ Error GDExtension::open_library(const String &p_path, const String &p_entry_symb
 			return ERR_CANT_CREATE;
 		}
 		FileAccess::set_hidden_attribute(copy_path, true);
+		library_copied = true;
 
 		// Save the copied path so it can be deleted later.
 		temp_lib_path = copy_path;
@@ -714,12 +714,20 @@ Error GDExtension::open_library(const String &p_path, const String &p_entry_symb
 	}
 #endif
 
-	Error err = OS::get_singleton()->open_dynamic_library(abs_path, library, true);
+	Error err = OS::get_singleton()->open_dynamic_library(abs_path, library, true, &library_path);
 	if (err != OK) {
 		ERR_PRINT("GDExtension dynamic library not found: " + abs_path);
 		return err;
 	}
 
+#if defined(WINDOWS_ENABLED) && defined(TOOLS_ENABLED)
+	// If we copied the file, let's change the library path to point at the original,
+	// because that's what we want to check to see if it's changed.
+	if (library_copied) {
+		library_path = library_path.get_base_dir() + "\\" + p_path.get_file();
+	}
+#endif
+
 	void *entry_funcptr = nullptr;
 
 	err = OS::get_singleton()->get_dynamic_library_symbol_handle(library, p_entry_symbol, entry_funcptr, false);
@@ -904,6 +912,8 @@ Error GDExtensionResourceLoader::load_gdextension_resource(const String &p_path,
 		return ERR_FILE_NOT_FOUND;
 	}
 
+	bool is_static_library = library_path.ends_with(".a") || library_path.ends_with(".xcframework");
+
 	if (!library_path.is_resource_file() && !library_path.is_absolute_path()) {
 		library_path = p_path.get_base_dir().path_join(library_path);
 	}
@@ -920,7 +930,7 @@ Error GDExtensionResourceLoader::load_gdextension_resource(const String &p_path,
 			FileAccess::get_modified_time(library_path));
 #endif
 
-	err = p_extension->open_library(library_path, entry_symbol);
+	err = p_extension->open_library(is_static_library ? String() : library_path, entry_symbol);
 	if (err != OK) {
 #if defined(WINDOWS_ENABLED) && defined(TOOLS_ENABLED)
 		// If the DLL fails to load, make sure that temporary DLL copies are cleaned up.
diff --git a/core/input/input.cpp b/core/input/input.cpp
index 2d48bdd4cf..257452b3d8 100644
--- a/core/input/input.cpp
+++ b/core/input/input.cpp
@@ -695,53 +695,34 @@ void Input::_parse_input_event_impl(const Ref<InputEvent> &p_event, bool p_is_em
 	}
 
 	for (const KeyValue<StringName, InputMap::Action> &E : InputMap::get_singleton()->get_action_map()) {
-		if (InputMap::get_singleton()->event_is_action(p_event, E.key)) {
-			Action &action = action_state[E.key];
-			bool is_joypad_axis = jm.is_valid();
-			bool is_pressed = false;
-			if (!p_event->is_echo()) {
-				if (p_event->is_action_pressed(E.key)) {
-					bool is_joypad_axis_valid_zone_enter = false;
-					if (is_joypad_axis) {
-						if (!action.axis_pressed) {
-							is_joypad_axis_valid_zone_enter = true;
-							action.pressed++;
-							action.axis_pressed = true;
-						}
-					} else {
-						action.pressed++;
-					}
-					if (action.pressed == 1 && (is_joypad_axis_valid_zone_enter || !is_joypad_axis)) {
-						action.pressed_physics_frame = Engine::get_singleton()->get_physics_frames();
-						action.pressed_process_frame = Engine::get_singleton()->get_process_frames();
-					}
-					is_pressed = true;
-				} else {
-					bool is_released = true;
-					if (is_joypad_axis) {
-						if (action.axis_pressed) {
-							action.axis_pressed = false;
-						} else {
-							is_released = false;
-						}
-					}
+		const int event_index = InputMap::get_singleton()->event_get_index(p_event, E.key);
+		if (event_index == -1) {
+			continue;
+		}
 
-					if (is_released) {
-						if (action.pressed == 1) {
-							action.released_physics_frame = Engine::get_singleton()->get_physics_frames();
-							action.released_process_frame = Engine::get_singleton()->get_process_frames();
-						}
-						action.pressed = MAX(action.pressed - 1, 0);
-					}
+		Action &action = action_state[E.key];
+		if (!p_event->is_echo()) {
+			if (p_event->is_action_pressed(E.key)) {
+				if (!action.pressed) {
+					action.pressed_physics_frame = Engine::get_singleton()->get_physics_frames();
+					action.pressed_process_frame = Engine::get_singleton()->get_process_frames();
 				}
-				action.exact = InputMap::get_singleton()->event_is_action(p_event, E.key, true);
-			}
+				action.pressed |= ((uint64_t)1 << event_index);
+			} else {
+				action.pressed &= ~((uint64_t)1 << event_index);
+				action.pressed &= ~(1 << MAX_EVENT); // Always release the event from action_press() method.
 
-			if (is_pressed || action.pressed == 0) {
-				action.strength = p_event->get_action_strength(E.key);
-				action.raw_strength = p_event->get_action_raw_strength(E.key);
+				if (!action.pressed) {
+					action.released_physics_frame = Engine::get_singleton()->get_physics_frames();
+					action.released_process_frame = Engine::get_singleton()->get_process_frames();
+				}
+				_update_action_strength(action, MAX_EVENT, 0.0);
+				_update_action_raw_strength(action, MAX_EVENT, 0.0);
 			}
+			action.exact = InputMap::get_singleton()->event_is_action(p_event, E.key, true);
 		}
+		_update_action_strength(action, event_index, p_event->get_action_strength(E.key));
+		_update_action_raw_strength(action, event_index, p_event->get_action_raw_strength(E.key));
 	}
 
 	if (event_dispatch_function) {
@@ -858,13 +839,13 @@ void Input::action_press(const StringName &p_action, float p_strength) {
 	// Create or retrieve existing action.
 	Action &action = action_state[p_action];
 
-	action.pressed++;
-	if (action.pressed == 1) {
+	if (!action.pressed) {
 		action.pressed_physics_frame = Engine::get_singleton()->get_physics_frames();
 		action.pressed_process_frame = Engine::get_singleton()->get_process_frames();
 	}
-	action.strength = p_strength;
-	action.raw_strength = p_strength;
+	action.pressed |= 1 << MAX_EVENT;
+	_update_action_strength(action, MAX_EVENT, p_strength);
+	_update_action_raw_strength(action, MAX_EVENT, p_strength);
 	action.exact = true;
 }
 
@@ -872,13 +853,15 @@ void Input::action_release(const StringName &p_action) {
 	// Create or retrieve existing action.
 	Action &action = action_state[p_action];
 
-	action.pressed--;
-	if (action.pressed == 0) {
-		action.released_physics_frame = Engine::get_singleton()->get_physics_frames();
-		action.released_process_frame = Engine::get_singleton()->get_process_frames();
+	action.pressed = 0;
+	action.strength = 0.0;
+	action.raw_strength = 0.0;
+	action.released_physics_frame = Engine::get_singleton()->get_physics_frames();
+	action.released_process_frame = Engine::get_singleton()->get_process_frames();
+	for (uint64_t i = 0; i <= MAX_EVENT; i++) {
+		action.strengths[i] = 0.0;
+		action.raw_strengths[i] = 0.0;
 	}
-	action.strength = 0.0f;
-	action.raw_strength = 0.0f;
 	action.exact = true;
 }
 
@@ -1207,6 +1190,38 @@ void Input::_axis_event(int p_device, JoyAxis p_axis, float p_value) {
 	parse_input_event(ievent);
 }
 
+void Input::_update_action_strength(Action &p_action, int p_event_index, float p_strength) {
+	ERR_FAIL_INDEX(p_event_index, (int)MAX_EVENT + 1);
+
+	float old_strength = p_action.strengths[p_event_index];
+	p_action.strengths[p_event_index] = p_strength;
+
+	if (p_strength > p_action.strength) {
+		p_action.strength = p_strength;
+	} else if (Math::is_equal_approx(old_strength, p_action.strength)) {
+		p_action.strength = p_strength;
+		for (uint64_t i = 0; i <= MAX_EVENT; i++) {
+			p_action.strength = MAX(p_action.strength, p_action.strengths[i]);
+		}
+	}
+}
+
+void Input::_update_action_raw_strength(Action &p_action, int p_event_index, float p_strength) {
+	ERR_FAIL_INDEX(p_event_index, (int)MAX_EVENT + 1);
+
+	float old_strength = p_action.raw_strengths[p_event_index];
+	p_action.raw_strengths[p_event_index] = p_strength;
+
+	if (p_strength > p_action.raw_strength) {
+		p_action.raw_strength = p_strength;
+	} else if (Math::is_equal_approx(old_strength, p_action.raw_strength)) {
+		p_action.raw_strength = p_strength;
+		for (uint64_t i = 0; i <= MAX_EVENT; i++) {
+			p_action.raw_strength = MAX(p_action.raw_strength, p_action.raw_strengths[i]);
+		}
+	}
+}
+
 Input::JoyEvent Input::_get_mapped_button_event(const JoyDeviceMapping &mapping, JoyButton p_button) {
 	JoyEvent event;
 
diff --git a/core/input/input.h b/core/input/input.h
index bedc3fa0e3..dd613c4877 100644
--- a/core/input/input.h
+++ b/core/input/input.h
@@ -44,6 +44,8 @@ class Input : public Object {
 
 	static Input *singleton;
 
+	static constexpr uint64_t MAX_EVENT = 31;
+
 public:
 	enum MouseMode {
 		MOUSE_MODE_VISIBLE,
@@ -103,11 +105,22 @@ private:
 		uint64_t pressed_process_frame = UINT64_MAX;
 		uint64_t released_physics_frame = UINT64_MAX;
 		uint64_t released_process_frame = UINT64_MAX;
-		int pressed = 0;
-		bool axis_pressed = false;
+		uint64_t pressed = 0;
 		bool exact = true;
 		float strength = 0.0f;
 		float raw_strength = 0.0f;
+		LocalVector<float> strengths;
+		LocalVector<float> raw_strengths;
+
+		Action() {
+			strengths.resize(MAX_EVENT + 1);
+			raw_strengths.resize(MAX_EVENT + 1);
+
+			for (uint64_t i = 0; i <= MAX_EVENT; i++) {
+				strengths[i] = 0.0;
+				raw_strengths[i] = 0.0;
+			}
+		}
 	};
 
 	HashMap<StringName, Action> action_state;
@@ -227,6 +240,8 @@ private:
 	JoyAxis _get_output_axis(String output);
 	void _button_event(int p_device, JoyButton p_index, bool p_pressed);
 	void _axis_event(int p_device, JoyAxis p_axis, float p_value);
+	void _update_action_strength(Action &p_action, int p_event_index, float p_strength);
+	void _update_action_raw_strength(Action &p_action, int p_event_index, float p_strength);
 
 	void _parse_input_event_impl(const Ref<InputEvent> &p_event, bool p_is_emulated);
 
diff --git a/core/input/input_map.cpp b/core/input/input_map.cpp
index ddfde0e7cd..78b9ada884 100644
--- a/core/input/input_map.cpp
+++ b/core/input/input_map.cpp
@@ -127,16 +127,21 @@ List<StringName> InputMap::get_actions() const {
 	return actions;
 }
 
-List<Ref<InputEvent>>::Element *InputMap::_find_event(Action &p_action, const Ref<InputEvent> &p_event, bool p_exact_match, bool *r_pressed, float *r_strength, float *r_raw_strength) const {
+List<Ref<InputEvent>>::Element *InputMap::_find_event(Action &p_action, const Ref<InputEvent> &p_event, bool p_exact_match, bool *r_pressed, float *r_strength, float *r_raw_strength, int *r_event_index) const {
 	ERR_FAIL_COND_V(!p_event.is_valid(), nullptr);
 
+	int i = 0;
 	for (List<Ref<InputEvent>>::Element *E = p_action.inputs.front(); E; E = E->next()) {
 		int device = E->get()->get_device();
 		if (device == ALL_DEVICES || device == p_event->get_device()) {
 			if (E->get()->action_match(p_event, p_exact_match, p_action.deadzone, r_pressed, r_strength, r_raw_strength)) {
+				if (r_event_index) {
+					*r_event_index = i;
+				}
 				return E;
 			}
 		}
+		i++;
 	}
 
 	return nullptr;
@@ -179,6 +184,7 @@ void InputMap::action_erase_event(const StringName &p_action, const Ref<InputEve
 	List<Ref<InputEvent>>::Element *E = _find_event(input_map[p_action], p_event, true);
 	if (E) {
 		input_map[p_action].inputs.erase(E);
+
 		if (Input::get_singleton()->is_action_pressed(p_action)) {
 			Input::get_singleton()->action_release(p_action);
 		}
@@ -216,7 +222,13 @@ bool InputMap::event_is_action(const Ref<InputEvent> &p_event, const StringName
 	return event_get_action_status(p_event, p_action, p_exact_match);
 }
 
-bool InputMap::event_get_action_status(const Ref<InputEvent> &p_event, const StringName &p_action, bool p_exact_match, bool *r_pressed, float *r_strength, float *r_raw_strength) const {
+int InputMap::event_get_index(const Ref<InputEvent> &p_event, const StringName &p_action, bool p_exact_match) const {
+	int index = -1;
+	event_get_action_status(p_event, p_action, p_exact_match, nullptr, nullptr, nullptr, &index);
+	return index;
+}
+
+bool InputMap::event_get_action_status(const Ref<InputEvent> &p_event, const StringName &p_action, bool p_exact_match, bool *r_pressed, float *r_strength, float *r_raw_strength, int *r_event_index) const {
 	HashMap<StringName, Action>::Iterator E = input_map.find(p_action);
 	ERR_FAIL_COND_V_MSG(!E, false, suggest_actions(p_action));
 
@@ -236,7 +248,7 @@ bool InputMap::event_get_action_status(const Ref<InputEvent> &p_event, const Str
 		return input_event_action->get_action() == p_action;
 	}
 
-	List<Ref<InputEvent>>::Element *event = _find_event(E->value, p_event, p_exact_match, r_pressed, r_strength, r_raw_strength);
+	List<Ref<InputEvent>>::Element *event = _find_event(E->value, p_event, p_exact_match, r_pressed, r_strength, r_raw_strength, r_event_index);
 	return event != nullptr;
 }
 
diff --git a/core/input/input_map.h b/core/input/input_map.h
index b4d5beacb3..6407ea489e 100644
--- a/core/input/input_map.h
+++ b/core/input/input_map.h
@@ -61,7 +61,7 @@ private:
 	HashMap<String, List<Ref<InputEvent>>> default_builtin_cache;
 	HashMap<String, List<Ref<InputEvent>>> default_builtin_with_overrides_cache;
 
-	List<Ref<InputEvent>>::Element *_find_event(Action &p_action, const Ref<InputEvent> &p_event, bool p_exact_match = false, bool *r_pressed = nullptr, float *r_strength = nullptr, float *r_raw_strength = nullptr) const;
+	List<Ref<InputEvent>>::Element *_find_event(Action &p_action, const Ref<InputEvent> &p_event, bool p_exact_match = false, bool *r_pressed = nullptr, float *r_strength = nullptr, float *r_raw_strength = nullptr, int *r_event_index = nullptr) const;
 
 	TypedArray<InputEvent> _action_get_events(const StringName &p_action);
 	TypedArray<StringName> _get_actions();
@@ -86,7 +86,8 @@ public:
 
 	const List<Ref<InputEvent>> *action_get_events(const StringName &p_action);
 	bool event_is_action(const Ref<InputEvent> &p_event, const StringName &p_action, bool p_exact_match = false) const;
-	bool event_get_action_status(const Ref<InputEvent> &p_event, const StringName &p_action, bool p_exact_match = false, bool *r_pressed = nullptr, float *r_strength = nullptr, float *r_raw_strength = nullptr) const;
+	int event_get_index(const Ref<InputEvent> &p_event, const StringName &p_action, bool p_exact_match = false) const;
+	bool event_get_action_status(const Ref<InputEvent> &p_event, const StringName &p_action, bool p_exact_match = false, bool *r_pressed = nullptr, float *r_strength = nullptr, float *r_raw_strength = nullptr, int *r_event_index = nullptr) const;
 
 	const HashMap<StringName, Action> &get_action_map() const;
 	void load_from_project_settings();
diff --git a/core/io/resource.cpp b/core/io/resource.cpp
index e0d42a274a..64fa597a67 100644
--- a/core/io/resource.cpp
+++ b/core/io/resource.cpp
@@ -90,6 +90,10 @@ String Resource::get_path() const {
 	return path_cache;
 }
 
+void Resource::set_path_cache(const String &p_path) {
+	path_cache = p_path;
+}
+
 String Resource::generate_scene_unique_id() {
 	// Generate a unique enough hash, but still user-readable.
 	// If it's not unique it does not matter because the saver will try again.
diff --git a/core/io/resource.h b/core/io/resource.h
index a9b1a88f6b..610c2150db 100644
--- a/core/io/resource.h
+++ b/core/io/resource.h
@@ -103,6 +103,7 @@ public:
 
 	virtual void set_path(const String &p_path, bool p_take_over = false);
 	String get_path() const;
+	void set_path_cache(const String &p_path); // Set raw path without involving resource cache.
 	_FORCE_INLINE_ bool is_built_in() const { return path_cache.is_empty() || path_cache.contains("::") || path_cache.begins_with("local://"); }
 
 	static String generate_scene_unique_id();
diff --git a/core/io/resource_format_binary.cpp b/core/io/resource_format_binary.cpp
index ea97e5ecce..2a33f723dc 100644
--- a/core/io/resource_format_binary.cpp
+++ b/core/io/resource_format_binary.cpp
@@ -774,6 +774,8 @@ Error ResourceLoaderBinary::load() {
 			res = Ref<Resource>(r);
 			if (!path.is_empty() && cache_mode != ResourceFormatLoader::CACHE_MODE_IGNORE) {
 				r->set_path(path, cache_mode == ResourceFormatLoader::CACHE_MODE_REPLACE); //if got here because the resource with same path has different type, replace it
+			} else if (!path.is_resource_file()) {
+				r->set_path_cache(path);
 			}
 			r->set_scene_unique_id(id);
 		}
diff --git a/core/io/resource_importer.h b/core/io/resource_importer.h
index 0089544caa..e17644058a 100644
--- a/core/io/resource_importer.h
+++ b/core/io/resource_importer.h
@@ -136,6 +136,7 @@ public:
 
 	virtual void get_import_options(const String &p_path, List<ImportOption> *r_options, int p_preset = 0) const = 0;
 	virtual bool get_option_visibility(const String &p_path, const String &p_option, const HashMap<StringName, Variant> &p_options) const = 0;
+	virtual void handle_compatibility_options(HashMap<StringName, Variant> &p_import_params) const {}
 	virtual String get_option_group_file() const { return String(); }
 
 	virtual Error import(const String &p_source_file, const String &p_save_path, const HashMap<StringName, Variant> &p_options, List<String> *r_platform_variants, List<String> *r_gen_files = nullptr, Variant *r_metadata = nullptr) = 0;
diff --git a/core/io/resource_loader.cpp b/core/io/resource_loader.cpp
index 6721ec0953..529128b9a2 100644
--- a/core/io/resource_loader.cpp
+++ b/core/io/resource_loader.cpp
@@ -341,6 +341,8 @@ void ResourceLoader::_thread_load_function(void *p_userdata) {
 	if (load_task.resource.is_valid()) {
 		if (load_task.cache_mode != ResourceFormatLoader::CACHE_MODE_IGNORE) {
 			load_task.resource->set_path(load_task.local_path);
+		} else if (!load_task.local_path.is_resource_file()) {
+			load_task.resource->set_path_cache(load_task.local_path);
 		}
 
 		if (load_task.xl_remapped) {
@@ -918,7 +920,7 @@ String ResourceLoader::_path_remap(const String &p_path, bool *r_translation_rem
 		}
 
 		// Fallback to p_path if new_path does not exist.
-		if (!FileAccess::exists(new_path)) {
+		if (!FileAccess::exists(new_path + ".import") && !FileAccess::exists(new_path)) {
 			WARN_PRINT(vformat("Translation remap '%s' does not exist. Falling back to '%s'.", new_path, p_path));
 			new_path = p_path;
 		}
diff --git a/core/object/object.cpp b/core/object/object.cpp
index 2e5b897bce..40df13849b 100644
--- a/core/object/object.cpp
+++ b/core/object/object.cpp
@@ -198,6 +198,7 @@ bool Object::_predelete() {
 	notification(NOTIFICATION_PREDELETE, true);
 	if (_predelete_ok) {
 		_class_name_ptr = nullptr; // Must restore, so constructors/destructors have proper class name access at each stage.
+		notification(NOTIFICATION_PREDELETE_CLEANUP, true);
 	}
 	return _predelete_ok;
 }
diff --git a/core/object/object.h b/core/object/object.h
index a444db0f70..7b53fcaa41 100644
--- a/core/object/object.h
+++ b/core/object/object.h
@@ -72,12 +72,12 @@ enum PropertyHint {
 	PROPERTY_HINT_COLOR_NO_ALPHA, ///< used for ignoring alpha component when editing a color
 	PROPERTY_HINT_OBJECT_ID,
 	PROPERTY_HINT_TYPE_STRING, ///< a type string, the hint is the base type to choose
-	PROPERTY_HINT_NODE_PATH_TO_EDITED_NODE, ///< so something else can provide this (used in scripts)
+	PROPERTY_HINT_NODE_PATH_TO_EDITED_NODE, // Deprecated.
 	PROPERTY_HINT_OBJECT_TOO_BIG, ///< object is too big to send
 	PROPERTY_HINT_NODE_PATH_VALID_TYPES,
 	PROPERTY_HINT_SAVE_FILE, ///< a file path must be passed, hint_text (optionally) is a filter "*.png,*.wav,*.doc,". This opens a save dialog
 	PROPERTY_HINT_GLOBAL_SAVE_FILE, ///< a file path must be passed, hint_text (optionally) is a filter "*.png,*.wav,*.doc,". This opens a save dialog
-	PROPERTY_HINT_INT_IS_OBJECTID,
+	PROPERTY_HINT_INT_IS_OBJECTID, // Deprecated.
 	PROPERTY_HINT_INT_IS_POINTER,
 	PROPERTY_HINT_ARRAY_TYPE,
 	PROPERTY_HINT_LOCALE_ID,
@@ -105,7 +105,7 @@ enum PropertyUsageFlags {
 	PROPERTY_USAGE_SCRIPT_VARIABLE = 1 << 12,
 	PROPERTY_USAGE_STORE_IF_NULL = 1 << 13,
 	PROPERTY_USAGE_UPDATE_ALL_IF_MODIFIED = 1 << 14,
-	PROPERTY_USAGE_SCRIPT_DEFAULT_VALUE = 1 << 15,
+	PROPERTY_USAGE_SCRIPT_DEFAULT_VALUE = 1 << 15, // Deprecated.
 	PROPERTY_USAGE_CLASS_IS_ENUM = 1 << 16,
 	PROPERTY_USAGE_NIL_IS_VARIANT = 1 << 17,
 	PROPERTY_USAGE_ARRAY = 1 << 18, // Used in the inspector to group properties as elements of an array.
@@ -115,7 +115,7 @@ enum PropertyUsageFlags {
 	PROPERTY_USAGE_NODE_PATH_FROM_SCENE_ROOT = 1 << 22,
 	PROPERTY_USAGE_RESOURCE_NOT_PERSISTENT = 1 << 23,
 	PROPERTY_USAGE_KEYING_INCREMENTS = 1 << 24, // Used in inspector to increment property when keyed in animation player.
-	PROPERTY_USAGE_DEFERRED_SET_RESOURCE = 1 << 25, // when loading, the resource for this property can be set at the end of loading.
+	PROPERTY_USAGE_DEFERRED_SET_RESOURCE = 1 << 25, // Deprecated.
 	PROPERTY_USAGE_EDITOR_INSTANTIATE_OBJECT = 1 << 26, // For Object properties, instantiate them when creating in editor.
 	PROPERTY_USAGE_EDITOR_BASIC_SETTING = 1 << 27, //for project or editor settings, show when basic settings are selected.
 	PROPERTY_USAGE_READ_ONLY = 1 << 28, // Mark a property as read-only in the inspector.
@@ -801,6 +801,8 @@ public:
 		NOTIFICATION_POSTINITIALIZE = 0,
 		NOTIFICATION_PREDELETE = 1,
 		NOTIFICATION_EXTENSION_RELOADED = 2,
+		// Internal notification to send after NOTIFICATION_PREDELETE, not bound to scripting.
+		NOTIFICATION_PREDELETE_CLEANUP = 3,
 	};
 
 	/* TYPE API */
diff --git a/core/object/script_language.cpp b/core/object/script_language.cpp
index 011f4203ea..5f53975bf6 100644
--- a/core/object/script_language.cpp
+++ b/core/object/script_language.cpp
@@ -39,10 +39,11 @@
 
 ScriptLanguage *ScriptServer::_languages[MAX_LANGUAGES];
 int ScriptServer::_language_count = 0;
+bool ScriptServer::languages_ready = false;
+Mutex ScriptServer::languages_mutex;
 
 bool ScriptServer::scripting_enabled = true;
 bool ScriptServer::reload_scripts_on_save = false;
-SafeFlag ScriptServer::languages_finished; // Used until GH-76581 is fixed properly.
 ScriptEditRequestFunction ScriptServer::edit_request_func = nullptr;
 
 void Script::_notification(int p_what) {
@@ -160,12 +161,13 @@ bool ScriptServer::is_scripting_enabled() {
 }
 
 ScriptLanguage *ScriptServer::get_language(int p_idx) {
+	MutexLock lock(languages_mutex);
 	ERR_FAIL_INDEX_V(p_idx, _language_count, nullptr);
-
 	return _languages[p_idx];
 }
 
 Error ScriptServer::register_language(ScriptLanguage *p_language) {
+	MutexLock lock(languages_mutex);
 	ERR_FAIL_NULL_V(p_language, ERR_INVALID_PARAMETER);
 	ERR_FAIL_COND_V_MSG(_language_count >= MAX_LANGUAGES, ERR_UNAVAILABLE, "Script languages limit has been reach, cannot register more.");
 	for (int i = 0; i < _language_count; i++) {
@@ -179,6 +181,8 @@ Error ScriptServer::register_language(ScriptLanguage *p_language) {
 }
 
 Error ScriptServer::unregister_language(const ScriptLanguage *p_language) {
+	MutexLock lock(languages_mutex);
+
 	for (int i = 0; i < _language_count; i++) {
 		if (_languages[i] == p_language) {
 			_language_count--;
@@ -219,17 +223,31 @@ void ScriptServer::init_languages() {
 		}
 	}
 
-	for (int i = 0; i < _language_count; i++) {
-		_languages[i]->init();
+	{
+		MutexLock lock(languages_mutex);
+
+		for (int i = 0; i < _language_count; i++) {
+			_languages[i]->init();
+		}
+
+		languages_ready = true;
 	}
 }
 
 void ScriptServer::finish_languages() {
+	MutexLock lock(languages_mutex);
+
 	for (int i = 0; i < _language_count; i++) {
 		_languages[i]->finish();
 	}
 	global_classes_clear();
-	languages_finished.set();
+
+	languages_ready = false;
+}
+
+bool ScriptServer::are_languages_initialized() {
+	MutexLock lock(languages_mutex);
+	return languages_ready;
 }
 
 void ScriptServer::set_reload_scripts_on_save(bool p_enable) {
@@ -241,7 +259,8 @@ bool ScriptServer::is_reload_scripts_on_save_enabled() {
 }
 
 void ScriptServer::thread_enter() {
-	if (!languages_finished.is_set()) {
+	MutexLock lock(languages_mutex);
+	if (!languages_ready) {
 		return;
 	}
 	for (int i = 0; i < _language_count; i++) {
@@ -250,7 +269,8 @@ void ScriptServer::thread_enter() {
 }
 
 void ScriptServer::thread_exit() {
-	if (!languages_finished.is_set()) {
+	MutexLock lock(languages_mutex);
+	if (!languages_ready) {
 		return;
 	}
 	for (int i = 0; i < _language_count; i++) {
@@ -538,9 +558,6 @@ void PlaceHolderScriptInstance::get_property_list(List<PropertyInfo> *p_properti
 	} else {
 		for (const PropertyInfo &E : properties) {
 			PropertyInfo pinfo = E;
-			if (!values.has(pinfo.name)) {
-				pinfo.usage |= PROPERTY_USAGE_SCRIPT_DEFAULT_VALUE;
-			}
 			p_properties->push_back(E);
 		}
 	}
diff --git a/core/object/script_language.h b/core/object/script_language.h
index 3e4041d173..85e64c8d62 100644
--- a/core/object/script_language.h
+++ b/core/object/script_language.h
@@ -52,9 +52,11 @@ class ScriptServer {
 
 	static ScriptLanguage *_languages[MAX_LANGUAGES];
 	static int _language_count;
+	static bool languages_ready;
+	static Mutex languages_mutex;
+
 	static bool scripting_enabled;
 	static bool reload_scripts_on_save;
-	static SafeFlag languages_finished; // Used until GH-76581 is fixed properly.
 
 	struct GlobalScriptClass {
 		StringName language;
@@ -98,8 +100,7 @@ public:
 
 	static void init_languages();
 	static void finish_languages();
-
-	static bool are_languages_finished() { return languages_finished.is_set(); }
+	static bool are_languages_initialized();
 };
 
 class PlaceHolderScriptInstance;
diff --git a/core/object/undo_redo.cpp b/core/object/undo_redo.cpp
index a8f2ac5bfe..3c1d4ef95e 100644
--- a/core/object/undo_redo.cpp
+++ b/core/object/undo_redo.cpp
@@ -301,6 +301,8 @@ void UndoRedo::commit_action(bool p_execute) {
 		return; //still nested
 	}
 
+	bool add_message = !merging;
+
 	if (merging) {
 		version--;
 		merging = false;
@@ -314,7 +316,7 @@ void UndoRedo::commit_action(bool p_execute) {
 	_redo(p_execute); // perform action
 	committing--;
 
-	if (callback && actions.size() > 0) {
+	if (add_message && callback && actions.size() > 0) {
 		callback(callback_ud, actions[actions.size() - 1].name);
 	}
 }
@@ -463,6 +465,10 @@ bool UndoRedo::has_redo() const {
 	return (current_action + 1) < actions.size();
 }
 
+bool UndoRedo::is_merging() const {
+	return merging;
+}
+
 uint64_t UndoRedo::get_version() const {
 	return version;
 }
diff --git a/core/object/undo_redo.h b/core/object/undo_redo.h
index 74a6bea732..b3a3322e4b 100644
--- a/core/object/undo_redo.h
+++ b/core/object/undo_redo.h
@@ -131,6 +131,8 @@ public:
 	bool has_undo() const;
 	bool has_redo() const;
 
+	bool is_merging() const;
+
 	uint64_t get_version() const;
 
 	void set_commit_notify_callback(CommitNotifyCallback p_callback, void *p_ud);
diff --git a/core/object/worker_thread_pool.cpp b/core/object/worker_thread_pool.cpp
index 2fcd0867e6..784acadab4 100644
--- a/core/object/worker_thread_pool.cpp
+++ b/core/object/worker_thread_pool.cpp
@@ -30,6 +30,7 @@
 
 #include "worker_thread_pool.h"
 
+#include "core/object/script_language.h"
 #include "core/os/os.h"
 #include "core/os/thread_safe.h"
 
@@ -60,6 +61,14 @@ void WorkerThreadPool::_process_task(Task *p_task) {
 		set_current_thread_safe_for_nodes(false);
 		pool_thread_index = thread_ids[Thread::get_caller_id()];
 		ThreadData &curr_thread = threads[pool_thread_index];
+		// Since the WorkerThreadPool is started before the script server,
+		// its pre-created threads can't have ScriptServer::thread_enter() called on them early.
+		// Therefore, we do it late at the first opportunity, so in case the task
+		// about to be run uses scripting, guarantees are held.
+		if (!curr_thread.ready_for_scripting && ScriptServer::are_languages_initialized()) {
+			ScriptServer::thread_enter();
+			curr_thread.ready_for_scripting = true;
+		}
 		task_mutex.lock();
 		p_task->pool_thread_index = pool_thread_index;
 		if (low_priority) {
diff --git a/core/object/worker_thread_pool.h b/core/object/worker_thread_pool.h
index d4d9387765..f323a979f7 100644
--- a/core/object/worker_thread_pool.h
+++ b/core/object/worker_thread_pool.h
@@ -106,6 +106,7 @@ private:
 		uint32_t index;
 		Thread thread;
 		Task *current_low_prio_task = nullptr;
+		bool ready_for_scripting = false;
 	};
 
 	TightLocalVector<ThreadData> threads;
diff --git a/core/os/os.cpp b/core/os/os.cpp
index 991b179e1f..c7390f14ff 100644
--- a/core/os/os.cpp
+++ b/core/os/os.cpp
@@ -490,6 +490,12 @@ bool OS::has_feature(const String &p_feature) {
 	}
 #endif
 
+#if defined(IOS_SIMULATOR)
+	if (p_feature == "simulator") {
+		return true;
+	}
+#endif
+
 	if (_check_internal_feature_support(p_feature)) {
 		return true;
 	}
diff --git a/core/string/string_name.cpp b/core/string/string_name.cpp
index 5a8df07410..658297d805 100644
--- a/core/string/string_name.cpp
+++ b/core/string/string_name.cpp
@@ -122,7 +122,7 @@ void StringName::unref() {
 	if (_data && _data->refcount.unref()) {
 		MutexLock lock(mutex);
 
-		if (_data->static_count.get() > 0) {
+		if (CoreGlobals::leak_reporting_enabled && _data->static_count.get() > 0) {
 			if (_data->cname) {
 				ERR_PRINT("BUG: Unreferenced static string to 0: " + String(_data->cname));
 			} else {
diff --git a/core/string/translation.cpp b/core/string/translation.cpp
index 02380c92bb..a443ed308d 100644
--- a/core/string/translation.cpp
+++ b/core/string/translation.cpp
@@ -520,11 +520,11 @@ String TranslationServer::get_country_name(const String &p_country) const {
 void TranslationServer::set_locale(const String &p_locale) {
 	locale = standardize_locale(p_locale);
 
+	ResourceLoader::reload_translation_remaps();
+
 	if (OS::get_singleton()->get_main_loop()) {
 		OS::get_singleton()->get_main_loop()->notification(MainLoop::NOTIFICATION_TRANSLATION_CHANGED);
 	}
-
-	ResourceLoader::reload_translation_remaps();
 }
 
 String TranslationServer::get_locale() const {
@@ -816,10 +816,11 @@ bool TranslationServer::is_pseudolocalization_enabled() const {
 void TranslationServer::set_pseudolocalization_enabled(bool p_enabled) {
 	pseudolocalization_enabled = p_enabled;
 
+	ResourceLoader::reload_translation_remaps();
+
 	if (OS::get_singleton()->get_main_loop()) {
 		OS::get_singleton()->get_main_loop()->notification(MainLoop::NOTIFICATION_TRANSLATION_CHANGED);
 	}
-	ResourceLoader::reload_translation_remaps();
 }
 
 void TranslationServer::set_editor_pseudolocalization(bool p_enabled) {
@@ -836,10 +837,11 @@ void TranslationServer::reload_pseudolocalization() {
 	pseudolocalization_suffix = GLOBAL_GET("internationalization/pseudolocalization/suffix");
 	pseudolocalization_skip_placeholders_enabled = GLOBAL_GET("internationalization/pseudolocalization/skip_placeholders");
 
+	ResourceLoader::reload_translation_remaps();
+
 	if (OS::get_singleton()->get_main_loop()) {
 		OS::get_singleton()->get_main_loop()->notification(MainLoop::NOTIFICATION_TRANSLATION_CHANGED);
 	}
-	ResourceLoader::reload_translation_remaps();
 }
 
 StringName TranslationServer::pseudolocalize(const StringName &p_message) const {
diff --git a/core/string/ustring.cpp b/core/string/ustring.cpp
index 9be7c04158..60e2d539f8 100644
--- a/core/string/ustring.cpp
+++ b/core/string/ustring.cpp
@@ -4699,11 +4699,16 @@ String String::property_name_encode() const {
 
 static const char32_t invalid_node_name_characters[] = { '.', ':', '@', '/', '\"', UNIQUE_NODE_PREFIX[0], 0 };
 
-String String::get_invalid_node_name_characters() {
+String String::get_invalid_node_name_characters(bool p_allow_internal) {
 	// Do not use this function for critical validation.
 	String r;
 	const char32_t *c = invalid_node_name_characters;
 	while (*c) {
+		if (p_allow_internal && *c == '@') {
+			c++;
+			continue;
+		}
+
 		if (c != invalid_node_name_characters) {
 			r += " ";
 		}
diff --git a/core/string/ustring.h b/core/string/ustring.h
index f45392eee1..897b06fc6d 100644
--- a/core/string/ustring.h
+++ b/core/string/ustring.h
@@ -437,7 +437,7 @@ public:
 	String property_name_encode() const;
 
 	// node functions
-	static String get_invalid_node_name_characters();
+	static String get_invalid_node_name_characters(bool p_allow_internal = false);
 	String validate_node_name() const;
 	String validate_identifier() const;
 	String validate_filename() const;
diff --git a/core/variant/variant.cpp b/core/variant/variant.cpp
index 09fb34e7c1..4c0212075b 100644
--- a/core/variant/variant.cpp
+++ b/core/variant/variant.cpp
@@ -1291,7 +1291,13 @@ void Variant::zero() {
 			break;
 
 		default:
+			Type prev_type = type;
 			this->clear();
+			if (type != prev_type) {
+				// clear() changes type to NIL, so it needs to be restored.
+				Callable::CallError ce;
+				Variant::construct(prev_type, *this, nullptr, 0, ce);
+			}
 			break;
 	}
 }