inAppBrowser event.url does not return current URL

Ionic Framework ionic-v3
1

I am trying to get the current URL of the user from an inAppBrowser, however it only returns to me the URL that was set when I initially opened the inAppBrowser not the current URL that the user is on. Any ideas how I solve this.

Here is my code.

authenticate(){
    const browser =  this.inAppBrowser.create("https://oauth.binary.com/oauth2/authorize?app_id=xxxxx",'_blank', 'location=yes');
    browser.on("loadstart").subscribe((event: InAppBrowserEvent)=> {
      this.currentURL = event.url;
      let url = event.url;

      this.liveToken = /token1=([^&]+)/.exec(url)[1];
      this.testToken = /token2=([^&]+)/.exec(url)[1];
      console.log(event);
      console.log(event.url);

      if(this.liveToken){
        browser.close();
      }
    })
  }
2

Did you find solution to this.?
I am also struggling with this issue.
In Emulator it works perfectly but in Android Device its not giving expected result.