Refresh button turns into an "X" when I hover over it?

This may be a dumb question and completely unrelated to Reddit, but I only see this behavior on Reddit.

When I move my mouse over to the "refresh" button on my browser (Chrome), it quickly turns into an "X" before I can click it.

You may have seen that "X" when your browser is currently loading or refreshing the page, but when it does this on its own, it doesn't actually refresh the page. I have to move my mouse off of the button and put it back again in order for it to show the refresh button.

Like I said, this may not be a Reddit related question, but I only see this behavior on Reddit. I have plenty of pages open that I periodically refresh and it works fine.