Switching between text inputs within Modal flickers on iOS

Created by: eozelius

I have a bootstrap modal that contains a form with text and email fields. Moving between inputs by clicking, or using ios keyboard tab, causes a 'jumping' effect. The entire modal seems to re-render or slide down, animate again, and then the correct field is focused. The issue seems to be related to height of modal, often the first 3-4 input fields work fine, and then the fields closer to the bottom will have this issue.

Steps to recreate

1. http://output.jsbin.com/pusayir
2. launch modal
3. focus/click field 7
4. focus/click field 6
5. focus/click field 5

System info: Apple ipad2, v9.3.1 Chrome: 50.0.2661.95 Bootstrap: v3.3.6