Sticky element is mispositioned when StickyContainer is within a position: relative container

[hepiyellow]

I'm submitting a ...

• [x] bug report
• [ ] feature request
• [ ] support request

If you're reporting a bug, please provide a minimal demonstration of the problem

Bug Demo

What is the current behavior?

When the <StickyContainer/> has an ancestor with position: relative, the using <Sticky relative/> causes the Sticky element to jump to viewport's top when sticked.

What is the expected or desired behavior?

To stay in <StickyContainer/>.

Why do you want this? What use case do you have?

My Page has an App wrapper (not in my control), and renders my page in a container with position: relative.

What is your environment?

• Version:

react-sticky
└── 6.0.3

• Browser: Chrome Version 71.0.3578.9

Is there anything else I should know?

[vcarl]

Ah I see, yeah that does appear to be a bug. I forked your demo to make it clearer what's happening. https://codesandbox.io/s/wq621mz9j7