message: mimetype backcompat
diff: @@ -22,7 +22,11 @@ import { MultiDocumentServiceFactory } from "./multiDocumentServiceFactory";
  async function attach(loader: Loader, url: string, host: Host) {
  const response = await loader.request({ url });
  - if (response.status !== 200 || response.mimeType !== "fluid/component") {
  + if (response.status !== 200 ||
  + !(
  + response.mimeType === "fluid/component" ||
  + response.mimeType === "prague/component"
  + )) {
  return;
  }
  