In iOS 10.1 and Safari 10.0.1 (and as far as I can tell only on iOS 10.1 and Safari 10.0.1) I've found a strange stinkbug invoving rotation of SVG elements. The bug is triggered by any rotate value which computes to a value divisible by 90 degrees.
But it gets weirder.
To experience, load circles.html in Safari 10.0.1 or iOS 10.1, read along, and start zooming. Tweet me and/or pull request if you notice it in any other iOS or Safari builds.
(on macOS 10.12.2 Beta)