• Renamed web-authn attrs
• Command-style events became native commands (2026-09-13): provider-fetch-trigger → --fetch; super-form-trigger / web-authn-trigger → --submit; content-drawer-open / -close / -toggle → --open / --close / --toggle (per-open props from the invoker's data-*, not detail); content-carousel-next / -back → --next / --back; include-content-reload / spa-route-reload / quark-sheet-reload → --reload; provider-geolocation-request / provider-orientation-request → --request; data-table-export → --export (options as data-file-type / data-file-name / data-full on the invoker); data-table-filter removed — write filter-value / filter-casing. Invoke with <button command="--verb" commandfor="id">, <event-handler command-name="--verb" target-ref="…">, <dismiss-watcher command-name="--close">, or new CommandEvent().
• content: stopped awaiting promises from module functions (2026-09-28): return a value or a node; for work that finishes later see Asynchronous work
• handle: names the listener (2026-09-28): event / target are not in scope inside a handle: call, which runs on every event and returns the listener; the listener receives the event
• match-nested matches its own path too (2026-09-29): route-href="/users" match-nested is active at /users, so a separate route for that path renders beside it and a 404 fallback stays off there
• A reload reports no move (2026-09-29): route data has move: null after a reload (was the last move before it), as on any page load that is not back / forward; no spa-manager-<move> event fires and the saved scroll offset is restored
• The outermost spa-manager owns scroll (2026-09-29): the browser's own scroll restoration is off while it is connected; a spa-route without a manager no longer scrolls, and spa-route.setScroll() is gone
• Scroll resets only when a route rendered (2026-09-29): a push / replace that renders nothing (a param change on a reuse route) keeps its position, and a #fragment target wins over the reset
• One View Transition per navigation (2026-09-29): nested managers join the outermost manager's; only that one fires spa-manager-will-transition / spa-manager-transition and carries is-transitioning
• spa-manager-will-transition and spa-manager-rendered also fire without a View Transition (2026-09-29): reduced motion, no API, no-transition, first paint. preventDefault() on spa-manager-will-transition holds the update, the first paint included, until updateRoutes(true) is called (updateRoutes() runs it without a View Transition); a nested manager's spa-manager-rendered does not bubble
• An update that only changes provisions runs no View Transition (2026-09-29): a same-route="reuse" param change no longer animates
• A query change provisions the route again (2026-09-29): spa-route-provision fires, the provision carries query, and a same-route="refresh" route renders again
• A closed content-drawer is visibility: hidden after its slide-out (2026-09-29): a custom transition on it must keep visibility 0s <duration>; a closed drawer shown in the layout needs visibility: visible
• Only an .absolute content-drawer styles its parent (2026-09-29): position: relative; overflow: clip (was every drawer, with overflow: hidden)
• A failed request logs one line (2026-09-29): an error status logs a warning, which the default log level hides; a network or parse failure logs an error
• A template or sheet URL that answers with an error status gives is-error and paints nothing (2026-09-29): the error page is no longer rendered as content
• keycode-filter holding only spaces matches no key (2026-09-29): write space for the space bar
• has-rendered waits for the first render (2026-09-29): spa-manager sets it once the first update with a render has settled: rendered, failed or hit render-timeout (was when that update started), so a loading shell hidden on it stays until then
• params holds placeholders and named groups only (2026-09-29): a capture group in a path pattern no longer shifts the names (/(a|b)/:id gives params.id its own segment), and a placeholder that did not match is left out (was the string "undefined")
• A template URL request outlives the element that started it (2026-09-29): an element that deactivates, reloads, disconnects or changes template-ref mid-load stops waiting; the request completes and fills the cache, and other elements on that URL finish loading (were left is-loading)
• The internal content-carousel prop autoPlayIntervalId is now _autoPlayIntervalId (2026-09-29): pause auto-play with auto-play-stopped
• is-fallback decides from the path (2026-09-30): it is on only when no other route in its spa-manager matches the current path; without a manager it now checks its document (or shadow root) instead of always activating, and another fallback, its own layout or a route inside its template no longer hold it off
• spa-manager keeps the fallback title in default-title (2026-09-30): the attribute appears on the element once a route retitles the page, and may be authored; the internal _defaultTitle prop is gone
• render-timeout shows a route still waiting for its ready-on event (2026-09-30): when it settles an update, delaying-ready is removed from that route and its ready waiters are released (the route stayed hidden until the event fired)
• A first mount into a host-ref selector no longer clears the host (2026-09-30): what the host already holds stays until the first render replaces it, and no did-unrender fires for it
• A rule no longer rewrites an attribute that already reads the same (2026-09-30): values are compared as written, so data-n: 0; over data-n="0" writes nothing: no mutation record, no attributeChangedCallback
• A preserve run no longer uses up @warn / @error (2026-09-30): the one report per element is left for a run with a value
• A property set before upgrade is kept (2026-09-30): a declared Neutron prop assigned before the element's definition loaded is applied at upgrade (was dropped)
• Element authors (2026-09-30): replaceNonTemplateChildren from kit-utils is typed boolean | "adopted", and an override of isResponsibleForReady gets two more callers to answer true for: "adopted" (prerendered content kept) and, on a route, "render-timeout"
• scopeQueriesToDocument is gone from @excom/nucleus-dom (2026-10-01): installShims() covers what it did; if you installed it on its own, call supportSelectors(window)