230998 2021-09-29 16:12:29 -0700 Allow IntersectionObserver API to specify root for individual targets 2022-02-09 10:14:22 -0800 1 1 1 Unclassified WebKit New Bugs WebKit Nightly Build Unspecified Unspecified NEW https://bugs.webkit.org/show_bug.cgi?id=208094 InRadar P2 Normal --- 1 nmouchtaris webkit-unassigned jonlee rbuis simon.fraser webkit-bug-importer oldest_to_newest 1798658 0 nmouchtaris 2021-09-29 16:12:29 -0700 IntersectionObserver API should allow the specification of multiple roots, depending on the target element. This is needed for lazy image loading, as for lazy load images in scrollable elements, we want to set their root to the scrollable element, not the viewport. The current implementation results in the images being loaded only once they partially enter the viewport, as their root is set to the top-level viewport, not the scrollable element. 1798659 1 nmouchtaris 2021-09-29 16:12:56 -0700 rdar://83693358 1798691 2 nmouchtaris 2021-09-29 17:16:42 -0700 https://github.com/w3c/IntersectionObserver/issues/431 1798698 3 nmouchtaris 2021-09-29 17:23:26 -0700 See that for image in scrollable div only gets loaded once it enters the viewport: https://codepen.io/nmoucht/pen/VwWgoPv.