Scrolling is not getting captured fully in FireFox

🐛 bug report

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Description of the problem

When scrolling on an embedded code sandbox on firefox, the scroll is not fully captured by the embed and it makes the containing page scroll with it.

How has this issue affected you? What are you trying to accomplish?

I have multiple embedded sandboxes as examples on the docs, and when scrolling through the code inside the sandbox the whole page navigates away :)

To Reproduce

Visit https://formvuelate.js.org/guide/schema-form.html#schema
Open a sandbox code and try scrolling up and down on firefox, the page moves with it

https://user-images.githubusercontent.com/14843771/111882304-d6705b80-89ac-11eb-8f2d-9c2de6420ea3.mp4

Link to sandbox: link (optional)

Your Environment

Reproduce the problem at the linked FormVueLate schema-form page using Firefox 86.0.1 on macOS and scroll inside an embedded CodeSandbox. Trace the embedded sandbox's scrolling behavior and verify that scrolling remains contained within the embed rather than moving the containing page; no source file or test is named in the issue.