diff --git a/core/crypto/crypto.cpp b/core/crypto/crypto.cpp
index 692bd133521..2f0c54763b0 100644
--- a/core/crypto/crypto.cpp
+++ b/core/crypto/crypto.cpp
@@ -231,8 +231,7 @@ Error ResourceFormatSaverCrypto::save(const Ref<Resource> &p_resource, const Str
 	if (cert.is_valid()) {
 		err = cert->save(p_path);
 	} else if (key.is_valid()) {
-		String el = p_path.get_extension().to_lower();
-		err = key->save(p_path, el == "pub");
+		err = key->save(p_path, p_path.has_extension("pub"));
 	} else {
 		ERR_FAIL_V(ERR_INVALID_PARAMETER);
 	}
diff --git a/core/extension/gdextension.cpp b/core/extension/gdextension.cpp
index d5222f7f315..c821f375b83 100644
--- a/core/extension/gdextension.cpp
+++ b/core/extension/gdextension.cpp
@@ -888,8 +888,7 @@ bool GDExtensionResourceLoader::handles_type(const String &p_type) const {
 }
 
 String GDExtensionResourceLoader::get_resource_type(const String &p_path) const {
-	String el = p_path.get_extension().to_lower();
-	if (el == "gdextension") {
+	if (p_path.has_extension("gdextension")) {
 		return "GDExtension";
 	}
 	return "";
diff --git a/core/io/json.cpp b/core/io/json.cpp
index 4f6891af72f..5d58e49f198 100644
--- a/core/io/json.cpp
+++ b/core/io/json.cpp
@@ -1593,8 +1593,7 @@ bool ResourceFormatLoaderJSON::handles_type(const String &p_type) const {
 }
 
 String ResourceFormatLoaderJSON::get_resource_type(const String &p_path) const {
-	String el = p_path.get_extension().to_lower();
-	if (el == "json") {
+	if (p_path.has_extension("json")) {
 		return "JSON";
 	}
 	return "";
diff --git a/core/io/resource_saver.cpp b/core/io/resource_saver.cpp
index 6e267a62443..8456a5819a3 100644
--- a/core/io/resource_saver.cpp
+++ b/core/io/resource_saver.cpp
@@ -105,7 +105,6 @@ Error ResourceSaver::save(const Ref<Resource> &p_resource, const String &p_path,
 	}
 	ERR_FAIL_COND_V_MSG(path.is_empty(), ERR_INVALID_PARAMETER, "Can't save resource to empty path. Provide non-empty path or a Resource with non-empty resource_path.");
 
-	String extension = path.get_extension();
 	Error err = ERR_FILE_UNRECOGNIZED;
 
 	for (int i = 0; i < saver_count; i++) {
diff --git a/core/io/translation_loader_po.cpp b/core/io/translation_loader_po.cpp
index 0f3cf852a49..8b970ba7e3e 100644
--- a/core/io/translation_loader_po.cpp
+++ b/core/io/translation_loader_po.cpp
@@ -368,7 +368,7 @@ bool TranslationLoaderPO::handles_type(const String &p_type) const {
 }
 
 String TranslationLoaderPO::get_resource_type(const String &p_path) const {
-	if (p_path.get_extension().to_lower() == "po" || p_path.get_extension().to_lower() == "mo") {
+	if (p_path.has_extension("po") || p_path.has_extension("mo")) {
 		return "Translation";
 	}
 	return "";
diff --git a/core/string/ustring.h b/core/string/ustring.h
index 8dbf593654f..eeedd3edfdb 100644
--- a/core/string/ustring.h
+++ b/core/string/ustring.h
@@ -519,6 +519,8 @@ public:
 	String get_basename() const;
 	String path_join(const String &p_path) const;
 	char32_t unicode_at(int p_idx) const;
+	bool has_extension(const char *p_ext) const { return get_extension().to_lower() == p_ext; }
+	bool has_extension(const String &p_ext) const { return get_extension().to_lower() == p_ext; }
 
 	CharString ascii(bool p_allow_extended = false) const;
 	// Parse an ascii string.
diff --git a/editor/export/editor_export_platform.cpp b/editor/export/editor_export_platform.cpp
index 541af413183..87cf9b86e42 100644
--- a/editor/export/editor_export_platform.cpp
+++ b/editor/export/editor_export_platform.cpp
@@ -1521,7 +1521,7 @@ Error EditorExportPlatform::export_project_files(const Ref<EditorExportPreset> &
 			// Just store it as it comes.
 
 			// Customization only happens if plugins did not take care of it before.
-			bool force_binary = convert_text_to_binary && (path.get_extension().to_lower() == "tres" || path.get_extension().to_lower() == "tscn");
+			bool force_binary = convert_text_to_binary && (path.has_extension("tres") || path.has_extension("tscn"));
 			String export_path = _export_customize(path, customize_resources_plugins, customize_scenes_plugins, export_cache, export_base_path, force_binary);
 
 			if (export_path != path) {
diff --git a/editor/import/3d/resource_importer_scene.cpp b/editor/import/3d/resource_importer_scene.cpp
index 1f58b05d795..0fc79d6e0b2 100644
--- a/editor/import/3d/resource_importer_scene.cpp
+++ b/editor/import/3d/resource_importer_scene.cpp
@@ -2514,7 +2514,7 @@ void ResourceImporterScene::get_import_options(const String &p_path, List<Import
 		}
 		script_ext_hint += "*." + E;
 	}
-	bool trimming_defaults_on = p_path.get_extension().to_lower() == "fbx";
+	bool trimming_defaults_on = p_path.has_extension("fbx");
 
 	r_options->push_back(ImportOption(PropertyInfo(Variant::BOOL, "nodes/apply_root_scale"), true));
 	r_options->push_back(ImportOption(PropertyInfo(Variant::FLOAT, "nodes/root_scale", PROPERTY_HINT_RANGE, "0.001,1000,0.001"), 1.0));
diff --git a/editor/project_manager/project_manager.cpp b/editor/project_manager/project_manager.cpp
index 9c1464351e2..42025f655ee 100644
--- a/editor/project_manager/project_manager.cpp
+++ b/editor/project_manager/project_manager.cpp
@@ -140,7 +140,7 @@ void ProjectManager::_notification(int p_what) {
 // Utility data.
 
 Ref<Texture2D> ProjectManager::_file_dialog_get_icon(const String &p_path) {
-	if (p_path.get_extension().to_lower() == "godot") {
+	if (p_path.has_extension("godot")) {
 		return singleton->icon_type_cache["GodotMonochrome"];
 	}
 
@@ -148,7 +148,7 @@ Ref<Texture2D> ProjectManager::_file_dialog_get_icon(const String &p_path) {
 }
 
 Ref<Texture2D> ProjectManager::_file_dialog_get_thumbnail(const String &p_path) {
-	if (p_path.get_extension().to_lower() == "godot") {
+	if (p_path.has_extension("godot")) {
 		return singleton->icon_type_cache["GodotFile"];
 	}
 
diff --git a/editor/scene/3d/gpu_particles_collision_sdf_editor_plugin.cpp b/editor/scene/3d/gpu_particles_collision_sdf_editor_plugin.cpp
index 7b2226c6e83..f32e31b1089 100644
--- a/editor/scene/3d/gpu_particles_collision_sdf_editor_plugin.cpp
+++ b/editor/scene/3d/gpu_particles_collision_sdf_editor_plugin.cpp
@@ -42,7 +42,6 @@ void GPUParticlesCollisionSDF3DEditorPlugin::_bake() {
 			if (path.is_empty()) {
 				path = "res://" + col_sdf->get_name() + "_data.exr";
 			} else {
-				String ext = path.get_extension();
 				path = path.get_basename() + "." + col_sdf->get_name() + "_data.exr";
 			}
 			probe_file->set_current_path(path);
diff --git a/editor/scene/3d/voxel_gi_editor_plugin.cpp b/editor/scene/3d/voxel_gi_editor_plugin.cpp
index e8c97c44f8a..c4ff434f289 100644
--- a/editor/scene/3d/voxel_gi_editor_plugin.cpp
+++ b/editor/scene/3d/voxel_gi_editor_plugin.cpp
@@ -44,7 +44,6 @@ void VoxelGIEditorPlugin::_bake() {
 			if (path.is_empty()) {
 				path = "res://" + voxel_gi->get_name() + "_data.res";
 			} else {
-				String ext = path.get_extension();
 				path = path.get_basename() + "." + voxel_gi->get_name() + "_data.res";
 			}
 			probe_file->set_current_path(path);
diff --git a/modules/dds/texture_loader_dds.cpp b/modules/dds/texture_loader_dds.cpp
index 15ff5eac0d5..8cc3f54ae6a 100644
--- a/modules/dds/texture_loader_dds.cpp
+++ b/modules/dds/texture_loader_dds.cpp
@@ -735,7 +735,7 @@ bool ResourceFormatDDS::handles_type(const String &p_type) const {
 }
 
 String ResourceFormatDDS::get_resource_type(const String &p_path) const {
-	if (p_path.get_extension().to_lower() == "dds") {
+	if (p_path.has_extension("dds")) {
 		return "Texture";
 	}
 	return "";
diff --git a/modules/fbx/editor/editor_scene_importer_ufbx.cpp b/modules/fbx/editor/editor_scene_importer_ufbx.cpp
index 48c2cbe5041..07273d99d1d 100644
--- a/modules/fbx/editor/editor_scene_importer_ufbx.cpp
+++ b/modules/fbx/editor/editor_scene_importer_ufbx.cpp
@@ -94,7 +94,7 @@ Variant EditorSceneFormatImporterUFBX::get_option_visibility(const String &p_pat
 void EditorSceneFormatImporterUFBX::get_import_options(const String &p_path,
 		List<ResourceImporter::ImportOption> *r_options) {
 	// Returns all the options when path is empty because that means it's for the Project Settings.
-	if (p_path.is_empty() || p_path.get_extension().to_lower() == "fbx") {
+	if (p_path.is_empty() || p_path.has_extension("fbx")) {
 		r_options->push_back(ResourceImporterScene::ImportOption(PropertyInfo(Variant::INT, "fbx/importer", PROPERTY_HINT_ENUM, "ufbx,FBX2glTF"), FBX_IMPORTER_UFBX));
 		r_options->push_back(ResourceImporterScene::ImportOption(PropertyInfo(Variant::BOOL, "fbx/allow_geometry_helper_nodes"), false));
 		r_options->push_back(ResourceImporterScene::ImportOption(PropertyInfo(Variant::INT, "fbx/embedded_image_handling", PROPERTY_HINT_ENUM, "Discard All Textures,Extract Textures,Embed as Basis Universal,Embed as Uncompressed", PROPERTY_USAGE_DEFAULT | PROPERTY_USAGE_UPDATE_ALL_IF_MODIFIED), FBXState::HANDLE_BINARY_EXTRACT_TEXTURES));
diff --git a/modules/gdscript/gdscript_analyzer.cpp b/modules/gdscript/gdscript_analyzer.cpp
index 3b7a994771a..08a6005faab 100644
--- a/modules/gdscript/gdscript_analyzer.cpp
+++ b/modules/gdscript/gdscript_analyzer.cpp
@@ -492,7 +492,7 @@ Error GDScriptAnalyzer::resolve_class_inheritance(GDScriptParser::ClassNode *p_c
 				}
 			} else if (ProjectSettings::get_singleton()->has_autoload(name) && ProjectSettings::get_singleton()->get_autoload(name).is_singleton) {
 				const ProjectSettings::AutoloadInfo &info = ProjectSettings::get_singleton()->get_autoload(name);
-				if (info.path.get_extension().to_lower() != GDScriptLanguage::get_singleton()->get_extension()) {
+				if (!info.path.has_extension(GDScriptLanguage::get_singleton()->get_extension())) {
 					push_error(vformat(R"(Singleton %s is not a GDScript.)", info.name), id);
 					return ERR_PARSE_ERROR;
 				}
diff --git a/modules/gdscript/gdscript_cache.cpp b/modules/gdscript/gdscript_cache.cpp
index 3e11c0060ee..3cbd817f993 100644
--- a/modules/gdscript/gdscript_cache.cpp
+++ b/modules/gdscript/gdscript_cache.cpp
@@ -76,7 +76,7 @@ Error GDScriptParserRef::raise_status(Status p_new_status) {
 				get_parser()->clear();
 				status = PARSED;
 				String remapped_path = ResourceLoader::path_remap(path);
-				if (remapped_path.get_extension().to_lower() == "gdc") {
+				if (remapped_path.has_extension("gdc")) {
 					Vector<uint8_t> tokens = GDScriptCache::get_binary_tokens(remapped_path);
 					source_hash = hash_djb2_buffer(tokens.ptr(), tokens.size());
 					result = get_parser()->parse_binary(tokens, path);
@@ -313,7 +313,7 @@ Ref<GDScript> GDScriptCache::get_shallow_script(const String &p_path, Error &r_e
 	Ref<GDScript> script;
 	script.instantiate();
 	script->set_path(p_path, true);
-	if (remapped_path.get_extension().to_lower() == "gdc") {
+	if (remapped_path.has_extension("gdc")) {
 		Vector<uint8_t> buffer = get_binary_tokens(remapped_path);
 		if (buffer.is_empty()) {
 			r_error = ERR_FILE_CANT_READ;
@@ -364,7 +364,7 @@ Ref<GDScript> GDScriptCache::get_full_script(const String &p_path, Error &r_erro
 	const String remapped_path = ResourceLoader::path_remap(p_path);
 
 	if (p_update_from_disk) {
-		if (remapped_path.get_extension().to_lower() == "gdc") {
+		if (remapped_path.has_extension("gdc")) {
 			Vector<uint8_t> buffer = get_binary_tokens(remapped_path);
 			if (buffer.is_empty()) {
 				r_error = ERR_FILE_CANT_READ;
diff --git a/modules/gdscript/gdscript_editor.cpp b/modules/gdscript/gdscript_editor.cpp
index 66bcfe4b37f..38f710ae1a8 100644
--- a/modules/gdscript/gdscript_editor.cpp
+++ b/modules/gdscript/gdscript_editor.cpp
@@ -1123,7 +1123,7 @@ static void _list_available_types(bool p_inherit_only, GDScriptParser::Completio
 
 	for (const KeyValue<StringName, ProjectSettings::AutoloadInfo> &E : autoloads) {
 		const ProjectSettings::AutoloadInfo &info = E.value;
-		if (!info.is_singleton || info.path.get_extension().to_lower() != "gd") {
+		if (!info.is_singleton || !info.path.has_extension("gd")) {
 			continue;
 		}
 		ScriptLanguage::CodeCompletionOption option(info.name, ScriptLanguage::CODE_COMPLETION_KIND_CLASS, ScriptLanguage::LOCATION_OTHER_USER_CODE);
diff --git a/modules/gdscript/tests/gdscript_test_runner.cpp b/modules/gdscript/tests/gdscript_test_runner.cpp
index f46f7b4dfbc..be2a0d8a3c4 100644
--- a/modules/gdscript/tests/gdscript_test_runner.cpp
+++ b/modules/gdscript/tests/gdscript_test_runner.cpp
@@ -282,7 +282,7 @@ bool GDScriptTestRunner::make_tests_for_dir(const String &p_dir) {
 			} else if (binary_tokens && next.ends_with(".textonly.gd")) {
 				next = dir->get_next();
 				continue;
-			} else if (next.get_extension().to_lower() == "gd") {
+			} else if (next.has_extension("gd")) {
 #ifndef DEBUG_ENABLED
 				// On release builds, skip tests marked as debug only.
 				Error open_err = OK;
diff --git a/modules/gltf/editor/editor_scene_importer_blend.cpp b/modules/gltf/editor/editor_scene_importer_blend.cpp
index af180ec16b5..89a01036163 100644
--- a/modules/gltf/editor/editor_scene_importer_blend.cpp
+++ b/modules/gltf/editor/editor_scene_importer_blend.cpp
@@ -344,7 +344,7 @@ Node *EditorSceneFormatImporterBlend::import_scene(const String &p_path, uint32_
 
 Variant EditorSceneFormatImporterBlend::get_option_visibility(const String &p_path, const String &p_scene_import_type, const String &p_option,
 		const HashMap<StringName, Variant> &p_options) {
-	if (p_path.get_extension().to_lower() != "blend") {
+	if (!p_path.has_extension("blend")) {
 		return true;
 	}
 
@@ -358,7 +358,7 @@ Variant EditorSceneFormatImporterBlend::get_option_visibility(const String &p_pa
 
 void EditorSceneFormatImporterBlend::get_import_options(const String &p_path, List<ResourceImporter::ImportOption> *r_options) {
 	// Returns all the options when path is empty because that means it's for the Project Settings.
-	if (!p_path.is_empty() && p_path.get_extension().to_lower() != "blend") {
+	if (!p_path.is_empty() && !p_path.has_extension("blend")) {
 		return;
 	}
 #define ADD_OPTION_BOOL(PATH, VALUE) \
diff --git a/modules/jpg/movie_writer_mjpeg.cpp b/modules/jpg/movie_writer_mjpeg.cpp
index e508796e38d..0114c13455f 100644
--- a/modules/jpg/movie_writer_mjpeg.cpp
+++ b/modules/jpg/movie_writer_mjpeg.cpp
@@ -40,7 +40,7 @@ AudioServer::SpeakerMode MovieWriterMJPEG::get_audio_speaker_mode() const {
 }
 
 bool MovieWriterMJPEG::handles_file(const String &p_path) const {
-	return p_path.get_extension().to_lower() == "avi";
+	return p_path.has_extension("avi");
 }
 
 void MovieWriterMJPEG::get_supported_extensions(List<String> *r_extensions) const {
diff --git a/modules/ktx/texture_loader_ktx.cpp b/modules/ktx/texture_loader_ktx.cpp
index 83176e71ca5..f71444f7783 100644
--- a/modules/ktx/texture_loader_ktx.cpp
+++ b/modules/ktx/texture_loader_ktx.cpp
@@ -602,7 +602,7 @@ bool ResourceFormatKTX::handles_type(const String &p_type) const {
 }
 
 String ResourceFormatKTX::get_resource_type(const String &p_path) const {
-	if (p_path.get_extension().to_lower() == "ktx" || p_path.get_extension().to_lower() == "ktx2") {
+	if (p_path.has_extension("ktx") || p_path.has_extension("ktx2")) {
 		return "ImageTexture";
 	}
 	return "";
diff --git a/modules/mono/csharp_script.cpp b/modules/mono/csharp_script.cpp
index ef0f4945d06..2515c3062ef 100644
--- a/modules/mono/csharp_script.cpp
+++ b/modules/mono/csharp_script.cpp
@@ -2927,7 +2927,7 @@ bool ResourceFormatLoaderCSharpScript::handles_type(const String &p_type) const
 }
 
 String ResourceFormatLoaderCSharpScript::get_resource_type(const String &p_path) const {
-	return p_path.get_extension().to_lower() == "cs" ? CSharpLanguage::get_singleton()->get_type() : "";
+	return p_path.has_extension("cs") ? CSharpLanguage::get_singleton()->get_type() : "";
 }
 
 Error ResourceFormatSaverCSharpScript::save(const Ref<Resource> &p_resource, const String &p_path, uint32_t p_flags) {
diff --git a/modules/theora/editor/movie_writer_ogv.cpp b/modules/theora/editor/movie_writer_ogv.cpp
index cfe6677300e..cbba4a88c93 100644
--- a/modules/theora/editor/movie_writer_ogv.cpp
+++ b/modules/theora/editor/movie_writer_ogv.cpp
@@ -101,7 +101,7 @@ AudioServer::SpeakerMode MovieWriterOGV::get_audio_speaker_mode() const {
 }
 
 bool MovieWriterOGV::handles_file(const String &p_path) const {
-	return p_path.get_extension().to_lower() == "ogv";
+	return p_path.has_extension("ogv");
 }
 
 void MovieWriterOGV::get_supported_extensions(List<String> *r_extensions) const {
diff --git a/modules/theora/video_stream_theora.cpp b/modules/theora/video_stream_theora.cpp
index 21a5f11815c..b610384496f 100644
--- a/modules/theora/video_stream_theora.cpp
+++ b/modules/theora/video_stream_theora.cpp
@@ -819,8 +819,7 @@ bool ResourceFormatLoaderTheora::handles_type(const String &p_type) const {
 }
 
 String ResourceFormatLoaderTheora::get_resource_type(const String &p_path) const {
-	String el = p_path.get_extension().to_lower();
-	if (el == "ogv") {
+	if (p_path.has_extension("ogv")) {
 		return "VideoStreamTheora";
 	}
 	return "";
diff --git a/scene/resources/compressed_texture.cpp b/scene/resources/compressed_texture.cpp
index e4d9c24326b..76bc95ebaba 100644
--- a/scene/resources/compressed_texture.cpp
+++ b/scene/resources/compressed_texture.cpp
@@ -486,7 +486,7 @@ bool ResourceFormatLoaderCompressedTexture2D::handles_type(const String &p_type)
 }
 
 String ResourceFormatLoaderCompressedTexture2D::get_resource_type(const String &p_path) const {
-	if (p_path.get_extension().to_lower() == "ctex") {
+	if (p_path.has_extension("ctex")) {
 		return "CompressedTexture2D";
 	}
 	return "";
@@ -670,7 +670,7 @@ bool ResourceFormatLoaderCompressedTexture3D::handles_type(const String &p_type)
 }
 
 String ResourceFormatLoaderCompressedTexture3D::get_resource_type(const String &p_path) const {
-	if (p_path.get_extension().to_lower() == "ctex3d") {
+	if (p_path.has_extension("ctex3d")) {
 		return "CompressedTexture3D";
 	}
 	return "";
@@ -844,15 +844,15 @@ CompressedTextureLayered::~CompressedTextureLayered() {
 
 Ref<Resource> ResourceFormatLoaderCompressedTextureLayered::load(const String &p_path, const String &p_original_path, Error *r_error, bool p_use_sub_threads, float *r_progress, CacheMode p_cache_mode) {
 	Ref<CompressedTextureLayered> ct;
-	if (p_path.get_extension().to_lower() == "ctexarray") {
+	if (p_path.has_extension("ctexarray")) {
 		Ref<CompressedTexture2DArray> c;
 		c.instantiate();
 		ct = c;
-	} else if (p_path.get_extension().to_lower() == "ccube") {
+	} else if (p_path.has_extension("ccube")) {
 		Ref<CompressedCubemap> c;
 		c.instantiate();
 		ct = c;
-	} else if (p_path.get_extension().to_lower() == "ccubearray") {
+	} else if (p_path.has_extension("ccubearray")) {
 		Ref<CompressedCubemapArray> c;
 		c.instantiate();
 		ct = c;
@@ -884,13 +884,13 @@ bool ResourceFormatLoaderCompressedTextureLayered::handles_type(const String &p_
 }
 
 String ResourceFormatLoaderCompressedTextureLayered::get_resource_type(const String &p_path) const {
-	if (p_path.get_extension().to_lower() == "ctexarray") {
+	if (p_path.has_extension("ctexarray")) {
 		return "CompressedTexture2DArray";
 	}
-	if (p_path.get_extension().to_lower() == "ccube") {
+	if (p_path.has_extension("ccube")) {
 		return "CompressedCubemap";
 	}
-	if (p_path.get_extension().to_lower() == "ccubearray") {
+	if (p_path.has_extension("ccubearray")) {
 		return "CompressedCubemapArray";
 	}
 	return "";
diff --git a/scene/resources/resource_format_text.cpp b/scene/resources/resource_format_text.cpp
index 4206d13ea97..7c608742e8b 100644
--- a/scene/resources/resource_format_text.cpp
+++ b/scene/resources/resource_format_text.cpp
@@ -1488,7 +1488,7 @@ void ResourceFormatLoaderText::get_classes_used(const String &p_path, HashSet<St
 }
 
 String ResourceFormatLoaderText::get_resource_type(const String &p_path) const {
-	String ext = p_path.get_extension().to_lower();
+	const String ext = p_path.get_extension().to_lower();
 	if (ext == "tscn") {
 		return "PackedScene";
 	} else if (ext != "tres") {
@@ -1510,8 +1510,7 @@ String ResourceFormatLoaderText::get_resource_type(const String &p_path) const {
 }
 
 String ResourceFormatLoaderText::get_resource_script_class(const String &p_path) const {
-	String ext = p_path.get_extension().to_lower();
-	if (ext != "tres") {
+	if (!p_path.has_extension("tres")) {
 		return String();
 	}
 
@@ -1529,8 +1528,7 @@ String ResourceFormatLoaderText::get_resource_script_class(const String &p_path)
 }
 
 ResourceUID::ID ResourceFormatLoaderText::get_resource_uid(const String &p_path) const {
-	String ext = p_path.get_extension().to_lower();
-
+	const String ext = p_path.get_extension().to_lower();
 	if (ext != "tscn" && ext != "tres") {
 		return ResourceUID::INVALID_ID;
 	}
diff --git a/scene/resources/shader.cpp b/scene/resources/shader.cpp
index dc07ce7bb5e..0088cf9ecca 100644
--- a/scene/resources/shader.cpp
+++ b/scene/resources/shader.cpp
@@ -338,8 +338,7 @@ bool ResourceFormatLoaderShader::handles_type(const String &p_type) const {
 }
 
 String ResourceFormatLoaderShader::get_resource_type(const String &p_path) const {
-	String el = p_path.get_extension().to_lower();
-	if (el == "gdshader") {
+	if (p_path.has_extension("gdshader")) {
 		return "Shader";
 	}
 	return "";
diff --git a/scene/resources/shader_include.cpp b/scene/resources/shader_include.cpp
index b03396bd6fe..a051683b537 100644
--- a/scene/resources/shader_include.cpp
+++ b/scene/resources/shader_include.cpp
@@ -121,8 +121,7 @@ bool ResourceFormatLoaderShaderInclude::handles_type(const String &p_type) const
 }
 
 String ResourceFormatLoaderShaderInclude::get_resource_type(const String &p_path) const {
-	String extension = p_path.get_extension().to_lower();
-	if (extension == "gdshaderinc") {
+	if (p_path.has_extension("gdshaderinc")) {
 		return "ShaderInclude";
 	}
 	return "";
diff --git a/servers/movie_writer/movie_writer_pngwav.cpp b/servers/movie_writer/movie_writer_pngwav.cpp
index 6f5e7401252..d39d3f7a679 100644
--- a/servers/movie_writer/movie_writer_pngwav.cpp
+++ b/servers/movie_writer/movie_writer_pngwav.cpp
@@ -45,7 +45,7 @@ void MovieWriterPNGWAV::get_supported_extensions(List<String> *r_extensions) con
 }
 
 bool MovieWriterPNGWAV::handles_file(const String &p_path) const {
-	return p_path.get_extension().to_lower() == "png";
+	return p_path.has_extension("png");
 }
 
 String MovieWriterPNGWAV::zeros_str(uint32_t p_index) {
diff --git a/tests/core/string/test_string.h b/tests/core/string/test_string.h
index 70f4eaf6efa..1d91239ad4b 100644
--- a/tests/core/string/test_string.h
+++ b/tests/core/string/test_string.h
@@ -1783,6 +1783,13 @@ TEST_CASE("[String] Path functions") {
 		CHECK(String(path[i]).simplify_path().get_base_dir().path_join(file[i]) == String(path[i]).simplify_path());
 	}
 
+	CHECK(String("res://test.png").has_extension("png"));
+	CHECK(String("res://test.PNG").has_extension("png"));
+	CHECK_FALSE(String("res://test.png").has_extension("jpg"));
+	CHECK_FALSE(String("res://test.png/README").has_extension("png"));
+	CHECK_FALSE(String("res://test.").has_extension("png"));
+	CHECK_FALSE(String("res://test").has_extension("png"));
+
 	static const char *file_name[3] = { "test.tscn", "test://.xscn", "?tes*t.scn" };
 	static const bool valid[3] = { true, false, false };
 	for (int i = 0; i < 3; i++) {