Actually, it turns out it's not even working right under Chrome either. The inspector isn't tall enough to show Properties, and it's not scrollable, so all I see is the "Properties" header with nothing under it. Here's what I'm seeing:

https://files.app.net/299dvuDv6.png

Is this supposed to scroll, or what?

Edit:

The issue with Safari is purely that the flexbox model requires the -webkit prefix, so it needs `display: -webkit-flex` and `-webkit-flex: 1`.

Edit 2:

I'll submit a pull request for the Safari issues shortly, I'm trying to see if I can figure out what's wrong with scrolling first.

Edit 3:

PR submitted. This fixes both Safari compatibility and scrolling for Chrome/Safari.