Created attachment 280040 [details] Source code Given a container of width < 100%, an overlay with -webkit-backdrop-filter: blur() applied, and an element underneath the overlay with a CSS animation applied, triggering that animation causes rendering distortion to occur. While this issue can be reproduced when other backdrop-filters are applied, it is most prominent with blur(). Example: http://liamdbz.com/webkit Source files with reproduction attached. OS: OS X 10.11.5 Safari: 9.1.1