demo · v141
Anchor Navigation
Click any anchor link below. If the target sits inside a closed <details> or a hidden=until-found region, the browser opens every ancestor — exactly to the target, not all the surrounding ones. The 141 algorithm update makes this reliable across deeper nestings the old code couldn't handle.
Anchor links:
Outer details
Inner details
Deepest details
#nested-deep target lives 3 levels deep. The whole chain opens on anchor navigation.
Sibling (was open)
#sibling-closed target — the algorithm leaves already-open siblings alone.
Outer with hidden=until-found inside
the algorithm in plain English
// When navigating to a fragment:
// 1. find the element matching the id
// 2. walk up its ancestor chain
// 3. for each closed , set open=""
// 4. for each [hidden=until-found], remove the attribute
// 5. scroll the element into view, focus if appropriate
//
// 141 fix: the walk now correctly handles slots and shadow boundaries
// without re-entering the same node (the infinite-loop bug).why this angle
Long structured documents (legal terms, API references, knowledge bases) increasingly mix <details> for performance with anchor-link navigation for permalinks. The revealing algorithm has to walk arbitrary nesting and stop cleanly. Pre-141 there was an edge case where a slot inside a custom element inside a details inside a hidden region could loop the walk. The fix is a guard; the user-visible result is "anchor links never hang the page."