--- # Bug 2051177: follow-up to bug 2052033's inset fake-border anchoring. The inner # ClipOut is anchored to the snapped element by insetting a "snap outset" equal # to the spread. If that outset is quantized (the original fix stored it as Au, # 1/60px), the reconstructed element edge shifts by up to half an app unit. When # an element edge lands exactly on a device-pixel tie (x.5), that shift flips the # rounding to the opposite pixel on the min (top/left) edges, leaving those sides # of the ring a pixel thin while the max (right/bottom) edges stay correct. # # Here every element edge is on an x.5 tie and the spread (1.875) is a half app # unit, so the Au bug makes the top and left of the ring thin. The == reference # places the element at the rounded (integer) position it snaps to: with the # outset kept at exact f32 precision both render an identical uniform ring; with # the Au-quantized outset only this file's top/left go thin, so the two differ. root: items: - type: stacking-context bounds: [0, 0, 250, 250] items: - type: rect bounds: [0, 0, 250, 250] color: [255, 255, 255] - type: box-shadow bounds: [20.5, 20.5, 200, 200] color: [0, 0, 0, 1] clip-mode: inset offset: [0, 0] blur-radius: 0 spread-radius: 1.875