message: Guard against possible undefined in LanguageMiddlewareFeature
diff: @@ -22,14 +22,15 @@ type RemapParameterType<M extends keyof RemapApi> = GetRemapType<NonNullable<Rem
  export class LanguageMiddlewareFeature implements IDisposable {
  private readonly _middlewares: LanguageMiddleware[];
  - private _registration: IDisposable;
  + private _registration: IDisposable | undefined;
  constructor() {
  this._middlewares = [];
  }
  public dispose(): void {
  - this._registration.dispose();
  + // this._registration should always be defined, but just in case we never register...
  + this._registration?.dispose();
  }
  public register(): void {
  