235904 2022-01-31 11:23:51 -0800 `scroll-snap-type: x mandatory` jittery 2022-02-07 18:35:37 -0800 1 1 1 Unclassified WebKit Scrolling Safari Technology Preview Unspecified macOS 12 NEW InRadar P2 Normal --- 1 bramus webkit-unassigned bfulgham mrobinson simon.fraser webkit-bug-importer zalan oldest_to_newest 1835608 0 bramus 2022-01-31 11:23:51 -0800 When checking out the MDN demos on https://developer.mozilla.org/en-US/docs/Web/CSS/scroll-snap-type with `scroll-snap-type: x mandatory` selected, it acts a bit jittery when slowish-ly scrolling over the scroll container and then releasing. Just before it snaps, you can see it jump back a little bit. See recording at https://www.youtube.com/watch?v=vLapfq0flMM You can see it really good at the 4 second, where scrolling back from box 3 to box 2. It jumps a little bit back, before snapping. 1836496 1 simon.fraser 2022-02-02 10:05:12 -0800 What Safari are you seeing this with? STP 139? 1836514 2 bramus 2022-02-02 10:33:07 -0800 Seeing this behavior in both of these versions (on macOS 12.1 (21C52)): - Stable: Version 15.2 (17612.3.6.1.6) - STP: Release 139 (Safari 15.4, WebKit 17613.1.14.41.2) 1836547 3 bramus 2022-02-02 11:23:29 -0800 Updated my machine and Safari TP. Seeing the same behavior on the latest macOS 12.2 (21D49) using STP Release 139 (Safari 15.4, WebKit 17613.1.14.41.3) 1838259 4 webkit-bug-importer 2022-02-07 11:24:19 -0800 <rdar://problem/88584478>