UserAgent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/61.0.3163.100 Safari/537.36

Example URL:

Steps to reproduce the problem:
Just run this demo:
http://plnkr.co/edit/Mvkb7mPnJEKSOJQdHORZ?p=preview

What is the expected behavior?
Main page should not scroll.

What went wrong?
Main page is scrolling when we focus on element from iframe, even if the iframe is totally included in the main page view.

Main page is not scrolling: 
- Firefox
- Edge

Main page is scrolling: 
- Chrome
- Safari
- Opera

Does it occur on multiple sites: Yes

Is it a problem with a plugin? No 

Did this work before? N/A 

Does this work in other browsers? Yes

Chrome version: 61.0.3163.100  Channel: stable
OS Version: 10.0
Flash Version: