GPU blur: the frosted-glass filter runs on the device

The blur filter - filter: blur(), the frosted-glass effect - now runs its blur on the GPU. It renders the content to the same padded region the software filter uses so the blur's edges line up, runs a GPU box blur that is pixel-identical to the software one, and composites the result, matching within a rounding level. The blur is a three-pass convolution, the single most expensive per-pixel effect on the modern web, and it is now hardware work. With clips, transforms, colour filters, and blur all on the GPU, the only common effect left on software is the drop-shadow filter. The GPU aspect moves 40 to 42. The overall holds at 57.