message: Use older JS syntax to fix Linux + Web.
diff: @@ -247,14 +247,14 @@ Filament.loadClassExtensions = function() {
  const engine = this.getEngine();
  const urlkeys = this.getResourceUrls();
  const urlset = new Set();
  - for (let i = 0; i < urlkeys.size(); i++) {
  + for (var i = 0; i < urlkeys.size(); i++) {
  const url = urlkeys.get(i);
  if (url) {
  urlset.add(url);
  }
  }
  const resourceLoader = new Filament.gltfio$ResourceLoader(engine);
  - Filament.fetch([...urlset], function() {
  + Filament.fetch(Array.from(urlset), function() {
  const finalize = function() {
  resourceLoader.loadResources(asset);
  @@ -273,7 +273,7 @@ Filament.loadClassExtensions = function() {
  finalize();
  }
  }, function(name) {
  - let buffer = getBufferDescriptor(name);
  + var buffer = getBufferDescriptor(name);
  resourceLoader.addResourceData(name, buffer);
  buffer.delete();
  if (onFetched) {
  