window_open_1.cs

 <button (click)="downloadAndDisplayPdf"> open your pdf </button>

private async downloadAndDisplayPdf(): void {
  Manager.GetIllustrationDownload()
  .then((response) => {
    // these lines let us take a pdf file and get a blob url that we can use to navigate to it directly in browser
    const pdfFile = new File([response.fileContent], response.fileName, { type: 'application/pdf', lastModified: Date.now() });
    const objectURL = URL.createObjectURL(pdfFile);
    
    window.open(objectUrl, "_blank")
  })
}