295011 2025-06-25 20:21:47 -0700 [css-anchor-position-1] position-visibility:anchors-visible does not work correctly for chained anchors 2025-08-18 05:42:25 -0700 1 1 1 Unclassified WebKit Layout and Rendering WebKit Local Build Unspecified Unspecified RESOLVED FIXED InRadar P2 Normal --- 289743 291856 1 fantasai.bugs koivisto bfulgham kiet.ho simon.fraser webkit-bug-importer zalan oldest_to_newest 2125938 0 fantasai.bugs 2025-06-25 20:21:47 -0700 Overview: We have some errors in how we invalidate for position-visibility, in response to dynamic changes and/or chained anchor relationships. Affected Tests: * https://wpt.live/css/css-anchor-position/position-visibility-anchors-visible-chained-001.html * https://wpt.live/css/css-anchor-position/position-visibility-anchors-visible-chained-002.html * https://wpt.live/css/css-anchor-position/position-visibility-anchors-visible-chained-003.html * https://wpt.live/css/css-anchor-position/position-visibility-anchors-visible-chained-004html * http://wpt.live/css/css-anchor-position/position-visibility-anchors-visible-change-anchor.html Specification Link: https://www.w3.org/TR/css-anchor-position/#position-visibility 2125939 1 webkit-bug-importer 2025-06-25 20:21:58 -0700 <rdar://problem/154354453> 2135066 2 kiet.ho 2025-08-07 18:15:58 -0700 Take position-visibility-anchors-visible-chained-001.html for example, the DOM tree looks like this: -- #scroll-container |-- #anchor1 (anchor named --a1) |-- #chained (anchorpos to --a1) |-- #anchor2 (anchor named --a2) |-- #target (anchorpos to --a2) So the anchor chain is #target -> #anchor2 which is child of #chained -> #anchor1 297286@main implements chained scroll adjustment but only when the element is both an anchor and anchorpos. In the above case, the anchor is children of anchorpos, so that change doesn't adjust scroll. 2137140 3 koivisto 2025-08-18 03:59:26 -0700 Pull request: https://github.com/WebKit/WebKit/pull/49529 2137144 4 ews-feeder 2025-08-18 05:42:22 -0700 Committed 298835@main (ed2498e01831): <https://commits.webkit.org/298835@main> Reviewed commits have been landed. Closing PR #49529 and removing active labels.