Webstites that i entered is not appearing in themableBrowser


  constructor(public barcodeScanner: BarcodeScanner, public themableBrowser: ThemeableBrowser){}

   openBrowser( ){
    const options: ThemeableBrowserOptions = {
      toolbar: {
          height: 44,
          color: '#f0f0f0ff'
      },
      title: {
          color: '#003264ff',
          showPageTitle: true,
          staticText: 'staticText'
      },
      backButton: {
          
          image: 'back',
          imagePressed: 'back_pressed',
          align: 'left',
          event: 'backPressed'
      },
      forwardButton: {
          image: 'forward',
          imagePressed: 'forward_pressed',
          align: 'right',
          event: 'forwardPressed'
      },
      closeButton: {
          image: 'close',
          imagePressed: 'close_pressed',
          align: 'left',
          event: 'closePressed'
      },
      customButtons: [
          {
              image: 'share',
              imagePressed: 'share_pressed',
              align: 'right',
              event: 'sharePressed'
          }
      ],
      menu: {
          image: 'menu',
          imagePressed: 'menu_pressed',
          title: 'MenuTitle',
          cancel: 'Cancel',
          align: 'right',
          items: [
              {
                  event: 'helloPressed',
                  label: 'Hello World!'
              },
              {
                  event: 'testPressed',
                  label: 'Test!'
              }
          ]
      }, 
      backButtonCanClose: true 
 };
    const browser: ThemeableBrowserObject = this.themableBrowser.create( 'https://ionic.io', '_blank',options);
    browser.on('closePressed').subscribe(res => {
      browser.close();
    })
  }

here is the home.page.ts ,and i installed latest version of themableBrowser then added array of providers. However, while i can see title name, the website content does not appear whichever site i wrote in create function. Moreover, when i try to generate in browser i can see websites content. Unfortunately, themableBrowser is not testable in the browser.
How can i figure the problem out?

Doğaç