position: fixed jump

If you scroll down this page, and click one of the links (which wont navigate anywhere, although the bug still occurs when it does navigate), the green box on the right will jump up to the top of the page showing the red box behind.

So what's the difference between the boxes?

The red box has the following CSS:

	position: fixed;
	top: 0;
	right: 0;
	height: 5em;
	width: 5em;
	background: red;
	

The red box has the following CSS:

	position: fixed;
	right: 0;
	height: 5em;
	width: 5em;
	background: green;
	

As you can see, the bug only occurs when the element has no top specified. Also, the problem occurs if you reload the page when scrolled (this can be used to reset the test too, by scrolling up and reloading).

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