241737 2022-06-17 18:26:40 -0700 Small programmatic scrolls with scroll snap don't scroll in WebKit 2026-01-12 09:02:36 -0800 1 1 1 Unclassified WebKit Scrolling Safari 15 Unspecified Unspecified NEW https://bugs.webkit.org/show_bug.cgi?id=270064 https://bugs.webkit.org/show_bug.cgi?id=293227 https://www.eightyone.co.nz/projects/safe-night-a-thon InRadar P2 Normal --- 1 emory.fierlinger webkit-unassigned dino graouts simon.fraser webkit-bug-importer oldest_to_newest 1876578 0 emory.fierlinger 2022-06-17 18:26:40 -0700 I have a dynamic horizontal slider on a website, half way down this page: https://www.eightyone.co.nz/projects/safe-night-a-thon When a user hovers over the left/right arrows, the browser is supposed to slowly move them along the slider. This works in both Chrome and Firefox, but not Webkit/Safari. After talking with Apple engineers at WWDC22, they have diagnosed this as a Webkit bug, and have told me to file it as such here. Here is the code: var amount = ''; function scroll() { $('#horizontal-scroll-parent').animate({ scrollLeft: amount }, 25, 'linear', function() { if (amount != '') { scroll(); } }); } $('#next').hover(function() { amount = '+=25'; scroll(); }, function() { amount = ''; }); $('#back').hover(function() { amount = '-=25'; scroll(); }, function() { amount = ''; }); 1876754 1 webkit-bug-importer 2022-06-20 02:29:07 -0700 <rdar://problem/95524733> 1876755 2 graouts 2022-06-20 02:31:15 -0700 What does the scroll function do in your code example? Is it actually performing scrolling by calling something like scrollTo() or changing some CSS properties to affect where things are positioned and simulate scrolling? 1876826 3 simon.fraser 2022-06-20 11:09:39 -0700 I think the page is doing small programmatic scrolls; in WebKit these end up snapping back to the nearest snap point, but in other browsers they are allowed to scroll. 1876827 4 simon.fraser 2022-06-20 11:10:54 -0700 The spec <https://drafts.csswg.org/css-scroll-snap/#overview> says "author can request a particular bias for the scrollport to land on a snap position after scrolling operations (including programmatic scrolls such as the scrollTo() method)." so we should investigate to see if WebKit is correct, or other browsers are correct.