Handle undefined default export when importing module

Fixes #4536

packages/node_modules/@node-red/editor-client/src/js/nodes.js

@@ -2217,7 +2217,7 @@ RED.nodes = (function() {
                                 set: registry.getNodeSet("node-red/unknown")
                             }
                         } else {
-                            if (subflow_denylist[parentId] || createNewIds || options.importMap[n.id] === "copy") {
+                            if (createNewIds || options.importMap[n.id] === "copy") {
                                 parentId = subflow.id;
                                 node.type = "subflow:"+parentId;
                                 node._def = registry.getNodeType(node.type);

packages/node_modules/@node-red/nodes/core/function/10-function.js

@@ -315,7 +315,7 @@ module.exports = function(RED) {
                     var spec = module.module;
                     if (spec && (spec !== "")) {
                         moduleLoadPromises.push(RED.import(module.module).then(lib => {
-                            sandbox[vname] = lib.default;
+                            sandbox[vname] = lib.default || lib;
                         }).catch(err => {
                             node.error(RED._("function.error.moduleLoadError",{module:module.spec, error:err.toString()}))
                             throw err;