diff --git a/modules/gltf/doc_classes/GLTFDocument.xml b/modules/gltf/doc_classes/GLTFDocument.xml
index 47ffc624bad9..a7497e9e5fff 100644
--- a/modules/gltf/doc_classes/GLTFDocument.xml
+++ b/modules/gltf/doc_classes/GLTFDocument.xml
@@ -95,6 +95,7 @@
 			<description>
 				Registers the given [GLTFDocumentExtension] instance with GLTFDocument. If [param first_priority] is [code]true[/code], this extension will be run first. Otherwise, it will be run last.
 				[b]Note:[/b] Like GLTFDocument itself, all GLTFDocumentExtension classes must be stateless in order to function properly. If you need to store data, use the [code]set_additional_data[/code] and [code]get_additional_data[/code] methods in [GLTFState] or [GLTFNode].
+				[b]Note:[/b] This method is static: Registered instances will be shared by all [GLTFDocument] instances. Beware that multiple instances of a single [GLTFDocumentExtension] class can often lead to unexpected behavior, and consider using [method get_all_gltf_document_extensions] to verify that only one instance of a given extension is registered.
 			</description>
 		</method>
 		<method name="unregister_gltf_document_extension" qualifiers="static">
@@ -102,6 +103,21 @@
 			<param index="0" name="extension" type="GLTFDocumentExtension" />
 			<description>
 				Unregisters the given [GLTFDocumentExtension] instance.
+				[b]Note:[/b] This method is static: Registering and unregistering instances will affect all [GLTFDocument] instances.
+			</description>
+		</method>
+		<method name="get_all_gltf_document_extensions" qualifiers="static">
+			<return type="Array[GLTFDocumentExtension]" />
+			<description>
+				Returns all registered [GLTFDocumentExtension] instances, including a default [GLTFDocumentExtensionConvertImporterMesh] instance at runtime.
+				[b]Note:[/b] This method is static: Registered instances will be shared by all [GLTFDocument] instances. Consider using this method to check if a given [GLTFDocumentExtension] is already registered.
+			</description>
+		</method>
+		<method name="unregister_all_gltf_document_extensions" qualifiers="static">
+			<return type="void" />
+			<description>
+				Unregisters all [GLTFDocumentExtension] instances, including the default [GLTFDocumentExtensionConvertImporterMesh] instance at runtime.
+				[b]Note:[/b] This method is static: Unregistering instances will affect all [GLTFDocument] instances.
 			</description>
 		</method>
 		<method name="write_to_filesystem">
diff --git a/modules/gltf/doc_classes/GLTFDocumentExtensionConvertImporterMesh.xml b/modules/gltf/doc_classes/GLTFDocumentExtensionConvertImporterMesh.xml
index 04075caba5b8..0c30c3f428c3 100644
--- a/modules/gltf/doc_classes/GLTFDocumentExtensionConvertImporterMesh.xml
+++ b/modules/gltf/doc_classes/GLTFDocumentExtensionConvertImporterMesh.xml
@@ -1,8 +1,12 @@
 <?xml version="1.0" encoding="UTF-8" ?>
 <class name="GLTFDocumentExtensionConvertImporterMesh" inherits="GLTFDocumentExtension" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noNamespaceSchemaLocation="../../../doc/class.xsd">
 	<brief_description>
+		A default [GLTFDocumentExtension] to convert [ImporterMeshInstance3D] nodes to [MeshInstance3D].
 	</brief_description>
 	<description>
+		This [GLTFDocumentExtension] is installed by default at runtime, but not in the editor. It converts all [ImporterMeshInstance3D] nodes and related [ImporterMesh] resources to [MeshInstance3D] nodes with [ArrayMesh] resources.
+
+		If it is important for a custom [GLTFDocumentExtension] to work with [ImporterMesh] at runtime, it is recommended to call [method GLTFDocument.register_gltf_document_extension] with the [code]true[/code] argument to prepend it to this default extension.
 	</description>
 	<tutorials>
 		<link title="Runtime file loading and saving">$DOCS_URL/tutorials/io/runtime_file_loading_and_saving.html</link>
diff --git a/modules/gltf/gltf_document.cpp b/modules/gltf/gltf_document.cpp
index 6da56616b715..4ad55ac4f422 100644
--- a/modules/gltf/gltf_document.cpp
+++ b/modules/gltf/gltf_document.cpp
@@ -8152,6 +8152,8 @@ void GLTFDocument::_bind_methods() {
 			&GLTFDocument::register_gltf_document_extension, DEFVAL(false));
 	ClassDB::bind_static_method("GLTFDocument", D_METHOD("unregister_gltf_document_extension", "extension"),
 			&GLTFDocument::unregister_gltf_document_extension);
+	ClassDB::bind_static_method("GLTFDocument", D_METHOD("unregister_all_gltf_document_extensions"), &GLTFDocument::unregister_all_gltf_document_extensions);
+	ClassDB::bind_static_method("GLTFDocument", D_METHOD("get_all_gltf_document_extensions"), &GLTFDocument::_get_all_gltf_document_extensions);
 	ClassDB::bind_static_method("GLTFDocument", D_METHOD("get_supported_gltf_extensions"),
 			&GLTFDocument::get_supported_gltf_extensions);
 }
@@ -8194,6 +8196,14 @@ Vector<Ref<GLTFDocumentExtension>> GLTFDocument::get_all_gltf_document_extension
 	return all_document_extensions;
 }
 
+TypedArray<Ref<GLTFDocumentExtension>> GLTFDocument::_get_all_gltf_document_extensions() {
+	TypedArray<Ref<GLTFDocumentExtension>> ret;
+	for (Ref<GLTFDocumentExtension> ext : all_document_extensions) {
+		ret.append(ext);
+	}
+	return ret;
+}
+
 Vector<String> GLTFDocument::get_supported_gltf_extensions() {
 	HashSet<String> set = get_supported_gltf_extensions_hashset();
 	Vector<String> vec;
diff --git a/modules/gltf/gltf_document.h b/modules/gltf/gltf_document.h
index a6d6caa3f0a7..fa68c1b156c0 100644
--- a/modules/gltf/gltf_document.h
+++ b/modules/gltf/gltf_document.h
@@ -85,6 +85,7 @@ class GLTFDocument : public Resource {
 	static void unregister_gltf_document_extension(Ref<GLTFDocumentExtension> p_extension);
 	static void unregister_all_gltf_document_extensions();
 	static Vector<Ref<GLTFDocumentExtension>> get_all_gltf_document_extensions();
+	static TypedArray<Ref<GLTFDocumentExtension>> _get_all_gltf_document_extensions();
 	static Vector<String> get_supported_gltf_extensions();
 	static HashSet<String> get_supported_gltf_extensions_hashset();