308648 2026-02-25 09:34:38 -0800 Absolutely positioned elements with intrinsic height incorrectly resolve percentage heights of children 2026-04-11 15:24:18 -0700 1 1 1 Unclassified WebKit CSS Other Unspecified Unspecified RESOLVED DUPLICATE 289876 https://github.com/web-platform-tests/wpt/pull/58161 InRadar P2 Normal --- 1 brandonstewart brandonstewart koivisto webkit-bug-importer zalan oldest_to_newest 2184835 0 brandonstewart 2026-02-25 09:34:38 -0800 When an absolutely positioned element has an intrinsic height value (fit-content, min-content, max-content), its children with percentage heights (e.g. height: 100%) should treat the parent's height as indefinite, since the parent's height depends on the content being sized. Instead, availableLogicalHeightForPercentageComputation() was treating any non-auto height as definite, causing percentage heights to resolve against the containing block's height rather than being treated as auto. This caused HeadlessUI popover panels (which use height: fit-content on an absolutely positioned flex container) to collapse to the navbar's height instead of sizing to their content. The fix excludes intrinsic height values from the "specified height" check in availableLogicalHeightForPercentageComputation(), so they are treated as indefinite for percentage resolution of children. 2184836 1 webkit-bug-importer 2026-02-25 09:34:45 -0800 <rdar://problem/171179193> 2184837 2 brandonstewart 2026-02-25 09:35:48 -0800 Pull request: https://github.com/WebKit/WebKit/pull/59424 2184912 3 ews-feeder 2026-02-25 12:51:28 -0800 Committed 308226@main (823b59d3140e): <https://commits.webkit.org/308226@main> Reviewed commits have been landed. Closing PR #59424 and removing active labels. 2186049 4 ntim 2026-03-02 00:12:48 -0800 Submitted web-platform-tests pull request: https://github.com/web-platform-tests/wpt/pull/58161 2199270 5 zalan 2026-04-11 15:24:18 -0700 This should have been re-opened when it got reverted. *** This bug has been marked as a duplicate of bug 289876 ***