Add checks after ResourceLoader::load()

editor/plugins/canvas_item_editor_plugin.cpp

@@ -5528,6 +5528,7 @@ void CanvasItemEditorViewport::_create_preview(const Vector<String> &files) cons
 	for (int i = 0; i < files.size(); i++) {
 		String path = files[i];
 		RES res = ResourceLoader::load(path);
+		ERR_FAIL_COND(res.is_null());
 		Ref<Texture> texture = Ref<Texture>(Object::cast_to<Texture>(*res));
 		Ref<PackedScene> scene = Ref<PackedScene>(Object::cast_to<PackedScene>(*res));
 		if (texture != NULL || scene != NULL) {

editor/plugins/spatial_editor_plugin.cpp

@@ -3230,6 +3230,7 @@ void SpatialEditorViewport::_create_preview(const Vector<String> &files) const {
 	for (int i = 0; i < files.size(); i++) {
 		String path = files[i];
 		RES res = ResourceLoader::load(path);
+		ERR_CONTINUE(res.is_null());
 		Ref<PackedScene> scene = Ref<PackedScene>(Object::cast_to<PackedScene>(*res));
 		Ref<Mesh> mesh = Ref<Mesh>(Object::cast_to<Mesh>(*res));
 		if (mesh != NULL || scene != NULL) {
@@ -3279,6 +3280,7 @@ bool SpatialEditorViewport::_cyclical_dependency_exists(const String &p_target_s
 
 bool SpatialEditorViewport::_create_instance(Node *parent, String &path, const Point2 &p_point) {
 	RES res = ResourceLoader::load(path);
+	ERR_FAIL_COND_V(res.is_null(), false);
 
 	Ref<PackedScene> scene = Ref<PackedScene>(Object::cast_to<PackedScene>(*res));
 	Ref<Mesh> mesh = Ref<Mesh>(Object::cast_to<Mesh>(*res));

editor/plugins/version_control_editor_plugin.cpp

@@ -380,6 +380,7 @@ void VersionControlEditorPlugin::fetch_available_vcs_addon_names() {
 
 		String path = ScriptServer::get_global_class_path(global_classes[i]);
 		Ref<Script> script = ResourceLoader::load(path);
+		ERR_FAIL_COND(script.is_null());
 
 		if (script->get_instance_base_type() == "EditorVCSInterface") {