NEW321467
[iOS] object-view-box view-transition overflow-visible path off by 1 device pixel 
https://bugs.webkit.org/show_bug.cgi?id=321467
Summary [iOS] object-view-box view-transition overflow-visible path off by 1 device p...
Alice Tang
Reported 2026-08-10 15:31:05 PDT
old-content-with-object-view-box.html and new-content-with-object-view-box.html (imported/w3c/web-platform-tests/css/css-view-transitions/) fail on iOS by 1 device pixel. Root cause: RenderViewTransitionCapture.cpp, in the overflow-visible paint path for ::view-transition-old/new with object-view-box: dstRect = snapRectToDevicePixels(computePaintRectForObjectViewBox(replacedContentRect), document().deviceScaleFactor()); On iOS's higher deviceScaleFactor (2x/3x vs. Mac), this snaps the view-box paint rect to a different device pixel than the reference image expects, producing a consistent 1px diff. Appears to be a device-pixel-snapping rounding difference, not a functional bug.
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Radar WebKit Bug Importer
Comment 1 2026-08-10 15:34:42 PDT
<rdar://problem/184557440>
Alice Tang
Comment 2 2026-08-10 16:53:44 PDT
Pull request: https://github.com/WebKit/WebKit/pull/71328
EWS
Comment 3 2026-08-11 14:52:57 PDT
Test gardening commit 318994@main (b11e8b5ae63a): <https://commits.webkit.org/318994@main> Reviewed commits have been landed. Closing PR #71328 and removing active labels.
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