Last tested version: 3.1
Apple’s Safari web browser supports the CSS3 border-radius property in order to round the corners of boxes. The curves it draws are anti-aliased (which is good), however it has one small glitch.
The outside of the border is antialised to the background colour of the box itself rather than the background of whatever is being displayed outside of the box. This results in a few oddly coloured pixels on the outside of the curves which may stand out depending on the contrast of the border and background colours.
The images below are enlarges snippets of a screenshot highlighting the problem. The first image shows the corner of a box with a white border and also has a drop-down shadow applied via the CSS3 box-shadow property (called -webkit-box-shadow in Safari until CSS3 is finalised). The second image is the same box but with a black border and without the shadow.
As you can see, the outside of the rounded borders fade to the same colour that the box uses as a background colour and not white, which was the background colour outside of the box (and beneath the shadow).