message: fix copy-pasta error
diff: @@ -20,6 +20,7 @@ import SdkConfig from '../../../SdkConfig';
  import AuthPage from "./AuthPage";
  import * as Matrix from "matrix-js-sdk";
  import {_td} from "../../../languageHandler";
  +import PlatformPeg from "../../../PlatformPeg";
  // translatable strings for Welcome pages
  _td("Sign in with SSO");
  @@ -43,7 +44,8 @@ export default class Welcome extends React.PureComponent {
  baseUrl: hsUrl,
  idBaseUrl: isUrl,
  });
  - const callbackUrl = this.getSSOCallbackUrl(tmpClient.getHomeserverUrl(), tmpClient.getIdentityServerUrl());
  + const plaf = PlatformPeg.get();
  + const callbackUrl = plaf.getSSOCallbackUrl(tmpClient.getHomeserverUrl(), tmpClient.getIdentityServerUrl());
  return (
  <AuthPage>
  