iOS back-to-app button on status bar not showing

I am redirecting a URL to open in safari using window.location.href in my ionic app
Until some time ago after the redirect, a button on iOS devices would show up "Back to " like this:

Recently I noticed that this button was missing when redirecting from the same page.
Major changes since i noticed it has disappeared:

  1. update in Xcode version which did not support swift 3 anymore.
  2. updated InAppBrowser plugin

I checked with older versions of Xcode, the button is still missing.

Does anyone have an idea what could be the issue here and solution?