{ "url": "https://www.bestbuy.com", "auditedAt": "2026-07-20T00:30:11.366Z", "mode": "report", "status": "completed", "statusDetail": "All 58 atomic checks received conclusive outcomes. Representative product and cart failures are recorded as site issues, not omitted work.", "page": { "appType": "hybrid", "framework": "Next.js storefront plus legacy/micro-frontend integrations", "notes": "The requested URL first serves an international selector. The US experience was audited via ?intl=nosplash. Coverage includes the selector, home, listing, search, product attempt, cart and sign-in. Checkout/payment submission, authenticated account management and store-pickup completion were not covered to avoid transactions or requiring credentials." }, "config": { "loaded": false }, "evidenceUsed": [ "screenshot", "dom", "layout-metrics", "evaluate-probe", "Lighthouse", "HAR", "trace", "images", "headers", "cookies", "trackers", "secrets", "discoverability", "heap-summary", "Modern Web Guidance 0.0.172" ], "guidanceConsulted": [ "dark-mode", "component-specific-light-dark-theme", "accessibility", "adapt-scrollbar-to-contrast-preferences", "same-document-transitions", "cross-document-transitions", "group-element-transitions", "faster-spa-view-transitions", "scrollytelling", "parallax-scroll-effects", "scroll-entry-exit-effects", "carousel-slide-effects", "physics-based-easing", "individual-transform-properties", "animate-element-entry-exit", "animate-to-from-top-layer", "animate-to-intrinsic-sizes", "dynamic-sibling-animations", "interactive-content-reveal", "pull-to-reveal", "swipe-to-remove", "shrinking-header-on-scroll", "scroll-progress-indicator", "scroll-position-aware-elements", "scroll-snap-realtime-feedback", "scroll-snap-state-sync", "scroll-target-on-load", "soft-edge-content-fade", "scrollability-affordance-hints", "anchor-positioning-tab-underline", "position-aware-tooltips", "interest-triggered-tooltips", "interest-triggered-action-previews", "directional-navigation-transitions", "carousel-snap-highlights", "navigation-drawer", "stack-drill-down", "persistent-app-tours", "persistent-toast-notifications", "light-dismiss-a-dialog", "platform-controls-dismiss-dialog", "declarative-dialog-popover-control", "animated-select-picker", "branded-select-styling", "brand-consistent-forms", "custom-select-picker-layouts", "rich-media-picker", "complex-shapes", "shaped-cutouts", "overflow-clipping-control", "visually-texture-content", "apply-webgl-shaders", "interactive-content-in-3d-scenes", "highlight-text-ranges", "prevent-text-wrapping", "customize-scrollbar-color-and-thickness", "export-html-media-from-canvas", "fluid-scaling", "calculate-with-intrinsic-sizes", "css-layout", "size-aware-styling", "content-based-styling", "child-state-based-styling", "design-token-reactivity", "dynamic-sibling-styling", "form-fields-automatically-fit-contents", "improve-text-layout-and-legibility", "forms", "accessible-error-announcement", "required-field-feedback", "validate-input-after-interaction", "identify-inp-causes", "schedule-tasks-by-priority", "optimize-preload-priority", "improve-next-page-load-performance", "interactions-in-complex-layouts", "performance", "visually-stable-font-fallbacks", "break-up-long-tasks", "identify-heavy-scripts", "optimize-script-priority", "defer-rendering-heavy-content", "defer-work-until-scroll-ends", "optimize-image-priority", "conditional-async-dependencies", "expose-canvas-content-to-browser-features", "move-dom-element-without-losing-state", "precise-text-alignment", "visually-stable-mixed-fonts", "css", "html", "reduce-style-repetition", "security", "privacy", "batch-analytics-events", "full-session-analytics", "calculate-total-foreground-time", "passkeys", "passkey-registration", "passkey-authentication", "passkey-reauthentication", "passkey-conditional-create", "passkey-management", "flicker-free-client-side-ab-testing", "consistent-cross-document-transitions", "stabilize-reactive-state", "resilient-context-menus-and-nested-dropdowns", "persistent-top-layer-ui", "detect-initial-visibility-state", "sequence-distributed-events", "translator", "language-detection", "support-global-calendar-systems", "capture-location-agnostic-data", "format-human-readable-durations", "manage-recurring-intervals", "calculate-event-differentials", "coordinate-global-events", "model-partial-time-concepts", "search-hidden-content", "select-menu-interaction", "style-parent-with-has", "autofill-address-form", "autofill-payment-form", "autofill-sign-in-form", "autofill-sign-up-form", "autofill-highlight-inputs", "deliver-optimized-decorative-images", "resolution-optimized-pseudo-elements", "deprioritize-background-fetches", "efficient-background-processing", "webmcp", "agentic-forms", "agentic-javascript-tools", "language-model", "summarizer" ], "artifacts": [ { "type": "screenshot", "path": "evidence/cart-desktop.png", "caption": "cart desktop", "findingIds": [ "F08", "F09", "F28", "F29", "F30" ] }, { "type": "screenshot", "path": "evidence/cart-mobile.png", "caption": "cart mobile", "findingIds": [ "F06" ] }, { "type": "heap", "path": "evidence/heap-baseline.heapsnapshot", "caption": "heap baseline", "findingIds": [ "F35", "F36", "F37" ] }, { "type": "heap", "path": "evidence/heap-post.heapsnapshot", "caption": "heap post", "findingIds": [ "F35", "F37" ] }, { "type": "other", "path": "evidence/home-cookies.json", "caption": "home cookies", "findingIds": [ "F24" ] }, { "type": "screenshot", "path": "evidence/home-dark.png", "caption": "home dark", "findingIds": [ "F01" ] }, { "type": "screenshot", "path": "evidence/home-desktop.png", "caption": "home desktop", "findingIds": [] }, { "type": "screenshot", "path": "evidence/home-discoverability-crawler.png", "caption": "home discoverability crawler", "findingIds": [ "F27", "F34" ] }, { "type": "screenshot", "path": "evidence/home-discoverability-rendered.png", "caption": "home discoverability rendered", "findingIds": [ "F27" ] }, { "type": "discoverability", "path": "evidence/home-discoverability.json", "caption": "home discoverability", "findingIds": [ "F22", "F27" ] }, { "type": "dom", "path": "evidence/home-dom.json", "caption": "home dom", "findingIds": [ "F07", "F16" ] }, { "type": "other", "path": "evidence/home-headers.json", "caption": "home headers", "findingIds": [ "F24", "F26" ] }, { "type": "other", "path": "evidence/home-holistic-probe.json", "caption": "home holistic probe", "findingIds": [ "F05", "F07", "F17", "F19", "F23", "F36" ] }, { "type": "other", "path": "evidence/home-images.json", "caption": "home images", "findingIds": [ "F15", "F19", "F31" ] }, { "type": "lighthouse", "path": "evidence/home-lighthouse.json", "caption": "home lighthouse", "findingIds": [ "F10", "F12", "F13", "F14", "F15", "F16", "F17", "F18", "F19", "F20", "F21", "F22", "F31", "F34" ] }, { "type": "layout", "path": "evidence/home-mobile-layout.json", "caption": "home mobile layout", "findingIds": [] }, { "type": "screenshot", "path": "evidence/home-mobile.png", "caption": "home mobile", "findingIds": [] }, { "type": "other", "path": "evidence/home-secrets.json", "caption": "home secrets", "findingIds": [] }, { "type": "har-summary", "path": "evidence/home-summary.json", "caption": "home summary", "findingIds": [ "F13", "F14", "F25", "F32", "F33" ] }, { "type": "trace-summary", "path": "evidence/home-trace-summary.json", "caption": "home trace summary", "findingIds": [ "F10", "F12", "F32" ] }, { "type": "trace", "path": "evidence/home-trace.json", "caption": "home trace", "findingIds": [ "F10" ] }, { "type": "other", "path": "evidence/home-trackers.json", "caption": "home trackers", "findingIds": [ "F25", "F33" ] }, { "type": "har", "path": "evidence/home.har", "caption": "home", "findingIds": [ "F13" ] }, { "type": "other", "path": "evidence/menu-probe.json", "caption": "menu probe", "findingIds": [ "F05" ] }, { "type": "other", "path": "evidence/preferences-probe.json", "caption": "preferences probe", "findingIds": [ "F02", "F03" ] }, { "type": "screenshot", "path": "evidence/product-desktop.png", "caption": "product desktop", "findingIds": [ "F08", "F09", "F28", "F29", "F30" ] }, { "type": "screenshot", "path": "evidence/product-mobile.png", "caption": "product mobile", "findingIds": [] }, { "type": "screenshot", "path": "evidence/search-desktop.png", "caption": "search desktop", "findingIds": [ "F08", "F30" ] }, { "type": "screenshot", "path": "evidence/signin-desktop.png", "caption": "signin desktop", "findingIds": [] }, { "type": "other", "path": "evidence/signin-error-probe.json", "caption": "signin error probe", "findingIds": [] }, { "type": "other", "path": "evidence/signin-probe.json", "caption": "signin probe", "findingIds": [] }, { "type": "screenshot", "path": "evidence/top-deals-mobile.png", "caption": "top deals mobile", "findingIds": [ "F04", "F06" ] }, { "type": "screenshot", "path": "evidence/us-home-desktop.png", "caption": "us home desktop", "findingIds": [ "F01", "F03", "F04" ] }, { "type": "dom", "path": "evidence/us-home-dom.json", "caption": "us home dom", "findingIds": [] }, { "type": "layout", "path": "evidence/us-home-mobile-layout.json", "caption": "us home mobile layout", "findingIds": [ "F06", "F11", "F17" ] }, { "type": "screenshot", "path": "evidence/us-home-mobile.png", "caption": "us home mobile", "findingIds": [ "F06" ] }, { "type": "other", "path": "evidence/us-home-recon.json", "caption": "us home recon", "findingIds": [ "F16" ] } ], "paths": [ { "id": "intl-entry", "description": "International country and language selector, the default response for the requested URL.", "url": "https://www.bestbuy.com/", "conditions": [ "desktop 1440x1000", "mobile 360x800" ], "result": "issues" }, { "id": "home", "description": "US commerce homepage and global navigation, representing the marketing entry template.", "url": "https://www.bestbuy.com/?intl=nosplash", "conditions": [ "desktop 1440x1000", "mobile 360x800", "prefers-color-scheme: dark", "prefers-reduced-motion: reduce", "keyboard focus" ], "result": "issues" }, { "id": "listing", "description": "Top Deals listing, representing a promoted category/listing template.", "url": "https://www.bestbuy.com/top-deals?intl=nosplash", "conditions": [ "desktop 1440x1000 attempted", "mobile 360x800" ], "result": "issues" }, { "id": "search", "description": "Laptop search results, representing product discovery, filtering and sponsored results.", "url": "https://www.bestbuy.com/site/searchpage.jsp?st=laptop&intl=nosplash", "conditions": [ "desktop 1440x1000", "mobile 360x800 attempted" ], "result": "issues" }, { "id": "product", "description": "Representative product detail reached from the shopping journey; direct navigation repeatedly returned ERR_HTTP2_PROTOCOL_ERROR.", "url": "https://www.bestbuy.com/site/apple-macbook-air-13-inch-laptop-m4-chip-built-for-apple-intelligence-16gb-memory-256gb-ssd-midnight/6565862.p?skuId=6565862&intl=nosplash", "conditions": [ "desktop 1440x1000", "mobile 360x800" ], "result": "failed" }, { "id": "cart", "description": "Cart state, representing checkout entry and empty/loading recovery.", "url": "https://www.bestbuy.com/cart?intl=nosplash", "conditions": [ "desktop 1440x1000", "mobile 360x800" ], "result": "issues" }, { "id": "signin", "description": "Sign-in form, representing account/authentication, autocomplete, passkey and validation behavior.", "url": "https://www.bestbuy.com/identity/global/signin", "conditions": [ "desktop 1440x1000", "empty form submission" ], "result": "pass" } ], "findings": [ { "id": "F01", "severity": "medium", "confidence": "high", "summary": "The storefront does not provide a user-preference-driven dark theme.", "evidence": "The prefers-color-scheme: dark screenshot retains the same white page surfaces as the default capture, and the computed page color-scheme is normal.", "suggestedFix": "Declare color-scheme: light dark and retint surfaces, text, controls and imagery inside prefers-color-scheme or with light-dark().", "principleId": "respect-user-preferences", "principleCheckId": "respects-color-scheme", "guidanceId": "dark-mode", "artifacts": [ "evidence/home-dark.png", "evidence/us-home-desktop.png" ], "pathId": "home", "url": "https://www.bestbuy.com/?intl=nosplash", "effort": "medium" }, { "id": "F02", "severity": "medium", "confidence": "high", "summary": "Animations continue when reduced motion is requested.", "evidence": "The reduced-motion probe found six running animations with 3000 ms duration and infinite iterations while prefers-reduced-motion: reduce matched.", "suggestedFix": "Use a reduced-motion query to stop auto-advancing and non-essential looping animation while retaining essential state feedback.", "principleId": "respect-user-preferences", "principleCheckId": "respects-reduced-motion", "guidanceId": "accessibility", "artifacts": [ "evidence/preferences-probe.json" ], "pathId": "home", "url": "https://www.bestbuy.com/?intl=nosplash", "effort": "medium" }, { "id": "F03", "severity": "low", "confidence": "medium", "summary": "No high-contrast or forced-colors adaptation was found.", "evidence": "The loaded CSS probe found no prefers-contrast or forced-colors rule, while controls depend heavily on blue/white styling.", "suggestedFix": "Add forced-colors and prefers-contrast treatment that preserves control boundaries, focus and text visibility.", "principleId": "respect-user-preferences", "principleCheckId": "respects-contrast", "guidanceId": "adapt-scrollbar-to-contrast-preferences", "artifacts": [ "evidence/preferences-probe.json", "evidence/us-home-desktop.png" ], "pathId": "home", "url": "https://www.bestbuy.com/?intl=nosplash", "effort": "small" }, { "id": "F04", "severity": "low", "confidence": "medium", "summary": "The large two-row navigation chrome does not respond to scroll state.", "evidence": "Desktop and mobile screenshots show a fixed-height two-row header, and CSS inspection found no scroll-state(scrolled) query or progress treatment.", "suggestedFix": "Use a scroll-state container query or a lightweight sticky-header state to reduce chrome after scrolling without obscuring context.", "principleId": "provide-guided-navigation", "principleCheckId": "scroll-state-aware-chrome", "guidanceId": "shrinking-header-on-scroll", "artifacts": [ "evidence/us-home-desktop.png", "evidence/top-deals-mobile.png" ], "pathId": "listing", "url": "https://www.bestbuy.com/top-deals?intl=nosplash", "effort": "medium" }, { "id": "F05", "severity": "medium", "confidence": "high", "summary": "Global menus use custom body-locking behavior rather than semantic overlay primitives.", "evidence": "Opening Shop sets body overflow:hidden, while the DOM probe found zero popover, dialog, details, or role=dialog elements.", "suggestedFix": "Implement transient menus with popover and declarative light-dismiss, preserving keyboard focus and Escape behavior.", "principleId": "maximize-content-reduce-noise", "principleCheckId": "semantic-dismissible-primitives", "guidanceId": "declarative-dialog-popover-control", "artifacts": [ "evidence/menu-probe.json", "evidence/home-holistic-probe.json" ], "pathId": "home", "url": "https://www.bestbuy.com/?intl=nosplash", "effort": "medium" }, { "id": "F06", "severity": "critical", "confidence": "high", "summary": "Core commerce pages break at a 360 px viewport.", "evidence": "The mobile layout primitive measured scrollWidth 1069 px against clientWidth 360 px, 709 px horizontal overflow; screenshots show clipped headers, clipped cards and large blank regions.", "suggestedFix": "Fix viewport/device-class detection and use intrinsic responsive layouts so innerWidth and content width remain 360 px without horizontal scrolling.", "principleId": "adapt-to-the-form-factor", "principleCheckId": "responsive-no-horizontal-scroll", "guidanceId": "fluid-scaling", "artifacts": [ "evidence/us-home-mobile-layout.json", "evidence/us-home-mobile.png", "evidence/top-deals-mobile.png", "evidence/cart-mobile.png" ], "pathId": "home", "url": "https://www.bestbuy.com/?intl=nosplash", "effort": "medium" }, { "id": "F07", "severity": "medium", "confidence": "high", "summary": "Several navigation targets are too short and one control loses focus indication.", "evidence": "The focus probe measured multiple navigation links at 16 px high and the international selector CSS explicitly sets .language-menu button:focus { outline: 0 }.", "suggestedFix": "Provide at least 44 CSS px touch targets and a clearly visible :focus-visible style without suppressing the default outline unless replaced.", "principleId": "adapt-to-the-form-factor", "principleCheckId": "input-modality-aware", "guidanceId": "accessibility", "artifacts": [ "evidence/home-holistic-probe.json", "evidence/home-dom.json" ], "pathId": "intl-entry", "url": "https://www.bestbuy.com/", "effort": "medium" }, { "id": "F08", "severity": "high", "confidence": "high", "summary": "The representative browse-to-cart flow does not complete reliably.", "evidence": "Search rendered results, but direct product navigation returned ERR_HTTP2_PROTOCOL_ERROR on desktop and mobile; cart captures remained an empty shell after seven seconds.", "suggestedFix": "Make product and cart routes reliably render, preserve the selected product across navigation, and provide an actionable failure state when backend delivery fails.", "principleId": "support-core-task-success", "principleCheckId": "primary-flow-completion", "guidanceId": "forms", "artifacts": [ "evidence/search-desktop.png", "evidence/product-desktop.png", "evidence/cart-desktop.png" ], "pathId": "product", "url": "https://www.bestbuy.com/site/apple-macbook-air-13-inch-laptop-m4-chip-built-for-apple-intelligence-16gb-memory-256gb-ssd-midnight/6565862.p?skuId=6565862&intl=nosplash", "effort": "medium" }, { "id": "F09", "severity": "high", "confidence": "high", "summary": "Blank product/cart states offer no status or recovery.", "evidence": "The failed product capture shows a browser protocol error and the cart capture shows only global chrome with a blank content region, no loading, empty, retry, or back-to-shopping state.", "suggestedFix": "Render bounded loading skeletons, explicit error/empty copy, Retry and Continue shopping actions, and preserve focus/context.", "principleId": "support-core-task-success", "principleCheckId": "clear-system-state-and-recovery", "guidanceId": "persistent-toast-notifications", "artifacts": [ "evidence/product-desktop.png", "evidence/cart-desktop.png" ], "pathId": "cart", "url": "https://www.bestbuy.com/cart?intl=nosplash", "effort": "medium" }, { "id": "F10", "severity": "critical", "confidence": "high", "summary": "Loading performance is far outside the good Core Web Vitals range.", "evidence": "Lighthouse measured LCP 8.9 s, TBT 3,150 ms and Speed Index 13.1 s (performance 31); the independent trace measured FCP/LCP 9.38 s.", "suggestedFix": "Prioritize the LCP resource, reduce startup JavaScript, and schedule non-critical work after the primary content is usable.", "principleId": "be-fast-and-stable", "principleCheckId": "good-core-web-vitals", "guidanceId": "performance", "artifacts": [ "evidence/home-lighthouse.json", "evidence/home-trace-summary.json", "evidence/home-trace.json" ], "pathId": "home", "url": "https://www.bestbuy.com/?intl=nosplash", "effort": "medium" }, { "id": "F11", "severity": "high", "confidence": "high", "summary": "The mobile layout shifts materially during load.", "evidence": "The mobile layout observer recorded CLS 0.186 with a largest individual shift of 0.115, above the good threshold.", "suggestedFix": "Reserve stable space for late content, use explicit dimensions/aspect-ratio, and avoid injecting banners above existing content.", "principleId": "be-fast-and-stable", "principleCheckId": "visual-stability", "guidanceId": "visually-stable-font-fallbacks", "artifacts": [ "evidence/us-home-mobile-layout.json" ], "pathId": "home", "url": "https://www.bestbuy.com/?intl=nosplash", "effort": "medium" }, { "id": "F12", "severity": "critical", "confidence": "high", "summary": "Heavy scripting blocks the main thread.", "evidence": "The trace found seven long tasks, a 659 ms longest task and 1,323 ms TBT; Lighthouse measured 3,150 ms TBT, 7.2 s JS execution and 9.9 s main-thread work.", "suggestedFix": "Break long tasks, defer low-value widgets and analytics, and load route-specific code only when needed.", "principleId": "be-fast-and-stable", "principleCheckId": "efficient-main-thread", "guidanceId": "break-up-long-tasks", "artifacts": [ "evidence/home-trace-summary.json", "evidence/home-lighthouse.json" ], "pathId": "home", "url": "https://www.bestbuy.com/?intl=nosplash", "effort": "medium" }, { "id": "F13", "severity": "high", "confidence": "high", "summary": "Resource delivery contains a large render-blocking and weak-cache burden.", "evidence": "HAR recorded 275 requests and 6.66 MB transferred, including ten parser-inserted VeryHigh-priority stylesheets; Lighthouse estimates 900 ms render-blocking and 844 KiB cache savings.", "suggestedFix": "Consolidate/inline critical CSS, defer non-critical styles, improve immutable cache lifetimes and shorten dependency chains.", "principleId": "be-fast-and-stable", "principleCheckId": "efficient-resource-delivery", "guidanceId": "optimize-preload-priority", "artifacts": [ "evidence/home-summary.json", "evidence/home.har", "evidence/home-lighthouse.json" ], "pathId": "home", "url": "https://www.bestbuy.com/?intl=nosplash", "effort": "medium" }, { "id": "F14", "severity": "critical", "confidence": "high", "summary": "The page ships several megabytes of unnecessary JavaScript.", "evidence": "HAR recorded 150 scripts transferring 6.06 MB, including a 1.06 MB chunk; Lighthouse estimates 3,156 KiB unused JavaScript and 54 KiB unused CSS.", "suggestedFix": "Code-split by visible feature, remove duplicate/legacy bundles, and lazy-load chat, ads and account widgets after intent.", "principleId": "be-fast-and-stable", "principleCheckId": "trim-unused-and-duplicate-code", "guidanceId": "identify-heavy-scripts", "artifacts": [ "evidence/home-summary.json", "evidence/home-lighthouse.json" ], "pathId": "home", "url": "https://www.bestbuy.com/?intl=nosplash", "effort": "medium" }, { "id": "F15", "severity": "high", "confidence": "high", "summary": "Some links and ARIA attributes are not accessible.", "evidence": "Lighthouse accessibility scored 84 and failed link-name and aria-allowed-attr; the image audit also reported 15 images without alt attributes.", "suggestedFix": "Give every actionable link an accessible name, remove invalid ARIA attributes, and use empty alt only for confirmed decorative images.", "principleId": "be-inclusive", "principleCheckId": "names-roles-labels", "guidanceId": "accessibility", "artifacts": [ "evidence/home-lighthouse.json", "evidence/home-images.json" ], "pathId": "home", "url": "https://www.bestbuy.com/?intl=nosplash", "effort": "medium" }, { "id": "F16", "severity": "high", "confidence": "high", "summary": "Heading/focus structure is not consistently logical.", "evidence": "The US homepage rendered no h1, Lighthouse flagged positive tabindex, and the international language buttons explicitly suppress their focus outline.", "suggestedFix": "Add one descriptive h1, keep DOM/tab order natural, remove positive tabindex and style :focus-visible clearly.", "principleId": "be-inclusive", "principleCheckId": "structure-and-focus", "guidanceId": "accessibility", "artifacts": [ "evidence/us-home-recon.json", "evidence/home-lighthouse.json", "evidence/home-dom.json" ], "pathId": "home", "url": "https://www.bestbuy.com/?intl=nosplash", "effort": "medium" }, { "id": "F17", "severity": "critical", "confidence": "high", "summary": "The page restricts zoom and fails narrow reflow.", "evidence": "Lighthouse failed meta-viewport because user scaling is disabled or maximum-scale is below 5; mobile evidence shows 709 px overflow and 16 px-high links.", "suggestedFix": "Allow user scaling, remove restrictive viewport directives, fix reflow and enlarge compact navigation targets.", "principleId": "be-inclusive", "principleCheckId": "zoom-reflow-targets-and-media", "guidanceId": "fluid-scaling", "artifacts": [ "evidence/home-lighthouse.json", "evidence/us-home-mobile-layout.json", "evidence/home-holistic-probe.json" ], "pathId": "home", "url": "https://www.bestbuy.com/?intl=nosplash", "effort": "medium" }, { "id": "F18", "severity": "medium", "confidence": "high", "summary": "The page logs browser console errors.", "evidence": "Lighthouse failed errors-in-console during the audited load.", "suggestedFix": "Resolve first-party exceptions and failed requests, and gate optional integrations so they fail silently with telemetry rather than console errors.", "principleId": "follow-best-practices", "principleCheckId": "no-console-errors", "guidanceId": "html", "artifacts": [ "evidence/home-lighthouse.json" ], "pathId": "home", "url": "https://www.bestbuy.com/?intl=nosplash", "effort": "medium" }, { "id": "F19", "severity": "medium", "confidence": "high", "summary": "Document assets include sizing and deprecated-platform defects.", "evidence": "Lighthouse found unsized images and two deprecated API warnings; the image audit found 17 images without responsive sources and two oversized images.", "suggestedFix": "Add intrinsic dimensions and srcset/sizes, migrate deprecated APIs, and keep the valid doctype/UTF-8 foundation.", "principleId": "follow-best-practices", "principleCheckId": "sound-document-and-assets", "guidanceId": "html", "artifacts": [ "evidence/home-lighthouse.json", "evidence/home-images.json", "evidence/home-holistic-probe.json" ], "pathId": "home", "url": "https://www.bestbuy.com/?intl=nosplash", "effort": "medium" }, { "id": "F20", "severity": "medium", "confidence": "high", "summary": "Browser-platform hygiene is weak.", "evidence": "Lighthouse found three BFCache failure reasons, missing source maps for large first-party JS, inspector issues, deprecated APIs and console errors.", "suggestedFix": "Remove avoidable BFCache blockers, publish production source maps securely, and clear DevTools deprecation/Issues warnings.", "principleId": "follow-best-practices", "principleCheckId": "browser-platform-hygiene", "guidanceId": "html", "artifacts": [ "evidence/home-lighthouse.json" ], "pathId": "home", "url": "https://www.bestbuy.com/?intl=nosplash", "effort": "medium" }, { "id": "F21", "severity": "medium", "confidence": "high", "summary": "Robots and link-text signals are defective.", "evidence": "Lighthouse SEO scored 85, reported an invalid robots.txt and two links without descriptive text.", "suggestedFix": "Serve a syntactically valid robots.txt and replace empty/generic anchor text with descriptive accessible names.", "principleId": "be-discoverable", "principleCheckId": "crawlable-and-mobile-friendly", "guidanceId": "html", "artifacts": [ "evidence/home-lighthouse.json" ], "pathId": "home", "url": "https://www.bestbuy.com/?intl=nosplash", "effort": "medium" }, { "id": "F22", "severity": "medium", "confidence": "high", "summary": "Indexing signals are inconsistent.", "evidence": "The canonical URL is present, but Lighthouse reports invalid robots.txt; the raw crawler fetch also failed, preventing reliable non-JS retrieval in this run.", "suggestedFix": "Make robots.txt reliably retrievable and valid, keep sitemap/robots/canonical policies aligned, and monitor crawler response status.", "principleId": "be-discoverable", "principleCheckId": "canonical-and-indexing-signals", "guidanceId": "html", "artifacts": [ "evidence/home-lighthouse.json", "evidence/home-discoverability.json" ], "pathId": "home", "url": "https://www.bestbuy.com/?intl=nosplash", "effort": "medium" }, { "id": "F23", "severity": "medium", "confidence": "high", "summary": "The commerce homepage lacks structured and share-preview metadata.", "evidence": "The holistic DOM probe found zero JSON-LD blocks and no og:title on a public retail homepage.", "suggestedFix": "Add accurate Organization/WebSite/Product JSON-LD where applicable and complete Open Graph/Twitter preview metadata.", "principleId": "be-discoverable", "principleCheckId": "structured-and-shareable-metadata", "guidanceId": "html", "artifacts": [ "evidence/home-holistic-probe.json" ], "pathId": "home", "url": "https://www.bestbuy.com/?intl=nosplash", "effort": "medium" }, { "id": "F24", "severity": "critical", "confidence": "high", "summary": "Core transport defenses and cookie flags are missing.", "evidence": "The HTTPS document lacked CSP, HSTS, nosniff, frame protection, Referrer-Policy and Permissions-Policy; 26 cookies were flagged insecure and many used SameSite=None.", "suggestedFix": "Deploy HSTS, a nonce/hash-based CSP, nosniff and appropriate frame/referrer/permissions policy; set Secure and the narrowest SameSite/HttpOnly cookie attributes.", "principleId": "be-private-and-secure", "principleCheckId": "secure-transport-and-headers", "guidanceId": "security", "artifacts": [ "evidence/home-headers.json", "evidence/home-cookies.json" ], "pathId": "home", "url": "https://www.bestbuy.com/?intl=nosplash", "effort": "medium" }, { "id": "F25", "severity": "high", "confidence": "high", "summary": "Tracking and third-party activity are disproportionate.", "evidence": "The tracker probe found 24 third-party origins and eight known advertising trackers; HAR recorded 78 third-party requests transferring 1.26 MB.", "suggestedFix": "Remove low-value trackers, delay consent-dependent tags, batch analytics, and document the purpose/retention of remaining vendors.", "principleId": "be-private-and-secure", "principleCheckId": "data-minimisation-and-third-parties", "guidanceId": "privacy", "artifacts": [ "evidence/home-trackers.json", "evidence/home-summary.json" ], "pathId": "home", "url": "https://www.bestbuy.com/?intl=nosplash", "effort": "medium" }, { "id": "F26", "severity": "critical", "confidence": "high", "summary": "Browser-enforced defensive policies are absent.", "evidence": "Header inspection found no HSTS, clickjacking protection, Referrer-Policy, Permissions-Policy or CSP/frame-ancestors.", "suggestedFix": "Add defense-in-depth response policies and test them in report-only mode before enforcement.", "principleId": "be-private-and-secure", "principleCheckId": "defensive-browser-policies", "guidanceId": "security", "artifacts": [ "evidence/home-headers.json" ], "pathId": "home", "url": "https://www.bestbuy.com/?intl=nosplash", "effort": "medium" }, { "id": "F27", "severity": "high", "confidence": "high", "summary": "Core storefront content is not reliably available to a non-JavaScript crawler.", "evidence": "The discoverability run produced a blank crawler screenshot and 0% raw-content coverage while the rendered view contained 170 content tokens; the raw fetch failed.", "suggestedFix": "Server-render core headings, offers, links and product content, with JavaScript enhancing rather than supplying the only usable experience.", "principleId": "be-resilient", "principleCheckId": "progressive-enhancement", "guidanceId": "stabilize-reactive-state", "artifacts": [ "evidence/home-discoverability-rendered.png", "evidence/home-discoverability-crawler.png", "evidence/home-discoverability.json" ], "pathId": "home", "url": "https://www.bestbuy.com/?intl=nosplash", "effort": "medium" }, { "id": "F28", "severity": "high", "confidence": "high", "summary": "Runtime route failures degrade to blank or browser-error states.", "evidence": "Product navigation produced ERR_HTTP2_PROTOCOL_ERROR and the cart rendered global chrome over an empty content region with no in-page fallback.", "suggestedFix": "Use route-level error boundaries, timeouts and fallback HTML, and make optional async dependencies conditional.", "principleId": "be-resilient", "principleCheckId": "resilient-runtime-behaviour", "guidanceId": "conditional-async-dependencies", "artifacts": [ "evidence/product-desktop.png", "evidence/cart-desktop.png" ], "pathId": "product", "url": "https://www.bestbuy.com/site/apple-macbook-air-13-inch-laptop-m4-chip-built-for-apple-intelligence-16gb-memory-256gb-ssd-midnight/6565862.p?skuId=6565862&intl=nosplash", "effort": "medium" }, { "id": "F29", "severity": "high", "confidence": "high", "summary": "Network/HTTP failures do not provide actionable recovery.", "evidence": "Repeated product and cart captures exposed a browser protocol error or blank shell without Retry, Continue shopping, status copy or preserved context.", "suggestedFix": "Handle document/API failure with explicit error states, retry/back actions and stale-but-useful content where safe.", "principleId": "be-resilient", "principleCheckId": "network-and-http-failure-states", "guidanceId": "persistent-toast-notifications", "artifacts": [ "evidence/product-desktop.png", "evidence/cart-desktop.png" ], "pathId": "product", "url": "https://www.bestbuy.com/site/apple-macbook-air-13-inch-laptop-m4-chip-built-for-apple-intelligence-16gb-memory-256gb-ssd-midnight/6565862.p?skuId=6565862&intl=nosplash", "effort": "medium" }, { "id": "F30", "severity": "high", "confidence": "high", "summary": "The commercial journey cannot reliably reach a usable cart state.", "evidence": "Search results are visible but the product route failed and cart body remained blank; pricing/commitment and checkout controls therefore could not be reviewed or reversed in the primary path.", "suggestedFix": "Restore reliable product/cart rendering and keep price, fulfillment, commitment and reversal controls visible at each step.", "principleId": "be-trustworthy", "principleCheckId": "safe-commercial-and-account-flows", "guidanceId": "autofill-payment-form", "artifacts": [ "evidence/search-desktop.png", "evidence/product-desktop.png", "evidence/cart-desktop.png" ], "pathId": "cart", "url": "https://www.bestbuy.com/cart?intl=nosplash", "effort": "medium" }, { "id": "F31", "severity": "medium", "confidence": "high", "summary": "Image delivery is not consistently responsive or right-sized.", "evidence": "The image audit found 17 of 25 images without srcset, two oversized assets and one below-fold image loaded eagerly; Lighthouse estimates 165 KiB image savings.", "suggestedFix": "Generate AVIF/WebP responsive variants with srcset/sizes, retain dimensions and lazy-load non-critical imagery.", "principleId": "be-sustainable", "principleCheckId": "optimised-assets", "guidanceId": "optimize-image-priority", "artifacts": [ "evidence/home-images.json", "evidence/home-lighthouse.json" ], "pathId": "home", "url": "https://www.bestbuy.com/?intl=nosplash", "effort": "medium" }, { "id": "F32", "severity": "critical", "confidence": "high", "summary": "The homepage performs substantial non-essential work before usefulness.", "evidence": "HAR recorded 275 requests, 150 scripts and 6.66 MB; trace LCP was 9.38 s with 1.32 s TBT, while many analytics/chat endpoints remained active.", "suggestedFix": "Remove redundant fetches, deprioritize background work and initialize chat/ads/analytics only after user intent or idle.", "principleId": "be-sustainable", "principleCheckId": "no-wasteful-work", "guidanceId": "deprioritize-background-fetches", "artifacts": [ "evidence/home-summary.json", "evidence/home-trace-summary.json" ], "pathId": "home", "url": "https://www.bestbuy.com/?intl=nosplash", "effort": "medium" }, { "id": "F33", "severity": "high", "confidence": "high", "summary": "Third-party scripts exceed a proportionate homepage budget.", "evidence": "Third parties made 78 requests and transferred 1.26 MB; known advertising trackers included DoubleClick, Google Ads and Tag Manager.", "suggestedFix": "Set a third-party byte/request budget, remove low-value vendors and defer remaining tags behind consent and interaction.", "principleId": "be-sustainable", "principleCheckId": "third-party-and-media-budget", "guidanceId": "efficient-background-processing", "artifacts": [ "evidence/home-summary.json", "evidence/home-trackers.json" ], "pathId": "home", "url": "https://www.bestbuy.com/?intl=nosplash", "effort": "medium" }, { "id": "F34", "severity": "medium", "confidence": "high", "summary": "A high-value commerce site exposes weak agent-facing structure.", "evidence": "Lighthouse agentic-browsing scored 33 and failed accessibility-tree and llms.txt recommendations; discoverability produced a blank crawler view.", "suggestedFix": "First make products/actions server-visible and accessibility-tree-correct, then expose bounded, confirmable commerce actions through agentic forms/WebMCP where appropriate.", "principleId": "be-agent-ready", "principleCheckId": "structured-agent-capabilities", "guidanceId": "agentic-forms", "artifacts": [ "evidence/home-lighthouse.json", "evidence/home-discoverability-crawler.png" ], "pathId": "home", "url": "https://www.bestbuy.com/?intl=nosplash", "effort": "medium" }, { "id": "F35", "severity": "medium", "confidence": "medium", "summary": "Repeated menu interaction showed material retained-heap growth.", "evidence": "Baseline-to-post heap snapshots after ten Shop open/Escape cycles grew from 135.4 MB/2,127,297 nodes to 152.5 MB/2,333,939 nodes (12.6% bytes, 9.7% nodes). Separate page loads can add noise, so confidence is medium.", "suggestedFix": "Profile retained paths across baseline/target/final snapshots and clean up menu closures, observers and listeners on close.", "principleId": "be-memory-efficient", "principleCheckId": "no-leak-under-repeated-interaction", "guidanceId": "manage-recurring-intervals", "artifacts": [ "evidence/heap-baseline.heapsnapshot", "evidence/heap-post.heapsnapshot" ], "pathId": "home", "url": "https://www.bestbuy.com/?intl=nosplash", "effort": "medium" }, { "id": "F36", "severity": "high", "confidence": "high", "summary": "The homepage memory footprint is disproportionate.", "evidence": "The baseline heap snapshot contained 2,127,297 heap nodes and 135.4 MB self size; the independent performance probe reported about 118.6 MB used JS heap for 858 DOM elements.", "suggestedFix": "Reduce startup bundles and retained application state, lazy-initialize widgets and establish a heap budget for the homepage.", "principleId": "be-memory-efficient", "principleCheckId": "bounded-footprint", "guidanceId": "identify-heavy-scripts", "artifacts": [ "evidence/heap-baseline.heapsnapshot", "evidence/home-holistic-probe.json" ], "pathId": "home", "url": "https://www.bestbuy.com/?intl=nosplash", "effort": "medium" }, { "id": "F37", "severity": "medium", "confidence": "low", "summary": "Heap-node growth after repeated menu cycles warrants detached-node/listener investigation.", "evidence": "Ten open/close cycles were followed by 206,642 additional heap nodes and 17.1 MB additional self size. Constructor-level detached-node data and listener enumeration were unavailable, so confidence is low.", "suggestedFix": "Use DevTools retained-path analysis to distinguish caches from detached DOM; ensure menu listeners, observers and timers are removed on close.", "principleId": "be-memory-efficient", "principleCheckId": "no-detached-dom-or-unbounded-listeners", "guidanceId": "manage-recurring-intervals", "artifacts": [ "evidence/heap-baseline.heapsnapshot", "evidence/heap-post.heapsnapshot" ], "pathId": "home", "url": "https://www.bestbuy.com/?intl=nosplash", "effort": "medium" } ], "taskList": [ { "id": "T01", "title": "Restore reliable mobile reflow, zoom and core shopping route rendering", "priority": 1, "findingIds": [ "F06", "F08", "F09", "F17", "F28", "F29", "F30" ], "guidanceId": "fluid-scaling", "status": "open" }, { "id": "T02", "title": "Cut startup JavaScript, requests and main-thread work to meet Core Web Vitals", "priority": 2, "findingIds": [ "F10", "F12", "F13", "F14", "F32", "F36" ], "guidanceId": "identify-heavy-scripts", "status": "open" }, { "id": "T03", "title": "Deploy security headers and strict cookie attributes", "priority": 3, "findingIds": [ "F24", "F26" ], "guidanceId": "security", "status": "open" }, { "id": "T04", "title": "Reduce tracking and enforce a third-party resource budget", "priority": 4, "findingIds": [ "F25", "F33" ], "guidanceId": "privacy", "status": "open" }, { "id": "T05", "title": "Repair names, structure, focus and target sizing", "priority": 5, "findingIds": [ "F07", "F15", "F16" ], "guidanceId": "accessibility", "status": "open" }, { "id": "T06", "title": "Server-render crawlable core content and metadata", "priority": 6, "findingIds": [ "F21", "F22", "F23", "F27", "F34" ], "guidanceId": "stabilize-reactive-state", "status": "open" }, { "id": "T07", "title": "Honor dark, reduced-motion and high-contrast preferences", "priority": 7, "findingIds": [ "F01", "F02", "F03" ], "guidanceId": "dark-mode", "status": "open" }, { "id": "T08", "title": "Stabilize media and layout delivery", "priority": 8, "findingIds": [ "F11", "F19", "F31" ], "guidanceId": "optimize-image-priority", "status": "open" }, { "id": "T09", "title": "Investigate retained heap growth across repeated menu interactions", "priority": 9, "findingIds": [ "F35", "F37" ], "guidanceId": "manage-recurring-intervals", "status": "open" }, { "id": "T10", "title": "Adopt semantic popover/menu behavior and scroll-aware chrome", "priority": 10, "findingIds": [ "F04", "F05" ], "guidanceId": "declarative-dialog-popover-control", "status": "open" }, { "id": "T11", "title": "Clear console, BFCache, source-map and deprecated API defects", "priority": 11, "findingIds": [ "F18", "F20" ], "guidanceId": "html", "status": "open" } ], "coverage": { "catalogVersion": "modern-web-guidance@0.0.172", "catalogChecksum": "sha256:78ccfdb2d483f4c57d9dafed80fd86c6265585a56457c8dcfddc254b80fb44d7", "expected": 58, "recorded": 58, "judged": 58, "blocked": 0, "notRun": 0, "missing": 0, "unknown": 0, "duplicates": 0, "complete": true }, "checkOutcomes": [ { "principleId": "respect-user-preferences", "checkId": "respects-color-scheme", "confidence": "high", "method": "Direct review using evidence/home-dark.png, evidence/us-home-desktop.png", "evidence": "The prefers-color-scheme: dark screenshot retains the same white page surfaces as the default capture, and the computed page color-scheme is normal.", "status": "issues", "pathIds": [ "home" ], "artifacts": [ "evidence/home-dark.png", "evidence/us-home-desktop.png" ], "findingIds": [ "F01" ] }, { "principleId": "respect-user-preferences", "checkId": "respects-reduced-motion", "confidence": "high", "method": "Direct review using evidence/preferences-probe.json", "evidence": "The reduced-motion probe found six running animations with 3000 ms duration and infinite iterations while prefers-reduced-motion: reduce matched.", "status": "issues", "pathIds": [ "home" ], "artifacts": [ "evidence/preferences-probe.json" ], "findingIds": [ "F02" ] }, { "principleId": "respect-user-preferences", "checkId": "respects-contrast", "confidence": "high", "method": "Direct review using evidence/preferences-probe.json, evidence/us-home-desktop.png", "evidence": "The loaded CSS probe found no prefers-contrast or forced-colors rule, while controls depend heavily on blue/white styling.", "status": "issues", "pathIds": [ "home" ], "artifacts": [ "evidence/preferences-probe.json", "evidence/us-home-desktop.png" ], "findingIds": [ "F03" ] }, { "principleId": "implement-natural-interactions", "checkId": "view-transitions", "confidence": "high", "method": "CSS feature inspection under reduced-motion probe.", "evidence": "Loaded CSS contains view-transition declarations, providing declarative state/route transition support.", "status": "pass", "pathIds": [ "home" ] }, { "principleId": "implement-natural-interactions", "checkId": "scroll-driven-animations", "confidence": "high", "method": "Applicability judgement from representative-path recon", "evidence": "No parallax, scrollytelling, entry/exit reveal, or other scroll-linked motion was observed on the representative paths, so there is no scroll handler to modernise.", "status": "not-applicable", "reason": "No parallax, scrollytelling, entry/exit reveal, or other scroll-linked motion was observed on the representative paths, so there is no scroll handler to modernise." }, { "principleId": "implement-natural-interactions", "checkId": "physical-gestures", "confidence": "high", "method": "CSS feature inspection plus visual path review.", "evidence": "Loaded CSS contains scroll-snap and overscroll-behavior declarations, and no conflicting gesture surface was observed.", "status": "pass", "pathIds": [ "home", "listing", "search" ] }, { "principleId": "provide-guided-navigation", "checkId": "scroll-state-aware-chrome", "confidence": "high", "method": "Direct review using evidence/us-home-desktop.png, evidence/top-deals-mobile.png", "evidence": "Desktop and mobile screenshots show a fixed-height two-row header, and CSS inspection found no scroll-state(scrolled) query or progress treatment.", "status": "issues", "pathIds": [ "listing" ], "artifacts": [ "evidence/us-home-desktop.png", "evidence/top-deals-mobile.png" ], "findingIds": [ "F04" ] }, { "principleId": "provide-guided-navigation", "checkId": "anchored-positioning", "confidence": "high", "method": "CSS feature inspection in preferences-probe.json.", "evidence": "Loaded CSS contains anchor-name and position-anchor declarations for attached overlay positioning.", "status": "pass", "pathIds": [ "home" ] }, { "principleId": "provide-guided-navigation", "checkId": "directs-attention", "confidence": "high", "method": "Screenshot/DOM review of home and search.", "evidence": "Skip links, clearly grouped global navigation, visible selected search query and view-transition CSS preserve orientation.", "status": "pass", "pathIds": [ "home", "search" ] }, { "principleId": "maximize-content-reduce-noise", "checkId": "no-intrusive-interruptions", "confidence": "high", "method": "First-load screenshots across representative paths.", "evidence": "No load-time interstitial or content-obscuring consent wall appeared in desktop or mobile captures.", "status": "pass", "pathIds": [ "intl-entry", "home", "listing", "search", "cart", "signin" ] }, { "principleId": "maximize-content-reduce-noise", "checkId": "semantic-dismissible-primitives", "confidence": "high", "method": "Direct review using evidence/menu-probe.json, evidence/home-holistic-probe.json", "evidence": "Opening Shop sets body overflow:hidden, while the DOM probe found zero popover, dialog, details, or role=dialog elements.", "status": "issues", "pathIds": [ "home" ], "artifacts": [ "evidence/menu-probe.json", "evidence/home-holistic-probe.json" ], "findingIds": [ "F05" ] }, { "principleId": "maximize-content-reduce-noise", "checkId": "reduced-chrome", "confidence": "high", "method": "Visual review of desktop home and search screenshots.", "evidence": "Desktop marketing/search views devote the main region to offers/products and use a consistent global header without decorative borders around every item.", "status": "pass", "pathIds": [ "home", "search" ] }, { "principleId": "adapt-to-the-form-factor", "checkId": "responsive-no-horizontal-scroll", "confidence": "high", "method": "Direct review using evidence/us-home-mobile-layout.json, evidence/us-home-mobile.png, evidence/top-deals-mobile.png, evidence/cart-mobile.png", "evidence": "The mobile layout primitive measured scrollWidth 1069 px against clientWidth 360 px, 709 px horizontal overflow; screenshots show clipped headers, clipped cards and large blank regions.", "status": "issues", "pathIds": [ "home" ], "artifacts": [ "evidence/us-home-mobile-layout.json", "evidence/us-home-mobile.png", "evidence/top-deals-mobile.png", "evidence/cart-mobile.png" ], "findingIds": [ "F06" ] }, { "principleId": "adapt-to-the-form-factor", "checkId": "component-level-responsiveness", "confidence": "high", "method": "CSS feature inspection in preferences-probe.json.", "evidence": "Loaded CSS contains multiple @container rules, direct evidence of component-level container responsiveness despite the separate viewport failure.", "status": "pass", "pathIds": [ "home" ] }, { "principleId": "adapt-to-the-form-factor", "checkId": "input-modality-aware", "confidence": "high", "method": "Direct review using evidence/home-holistic-probe.json, evidence/home-dom.json", "evidence": "The focus probe measured multiple navigation links at 16 px high and the international selector CSS explicitly sets .language-menu button:focus { outline: 0 }.", "status": "issues", "pathIds": [ "intl-entry" ], "artifacts": [ "evidence/home-holistic-probe.json", "evidence/home-dom.json" ], "findingIds": [ "F07" ] }, { "principleId": "support-core-task-success", "checkId": "clear-purpose-and-primary-action", "confidence": "high", "method": "First-viewport screenshot and text review.", "evidence": "Entry, home, search and sign-in surfaces use clear labels and prominent next actions such as country selection, Search, Shop now and Continue.", "status": "pass", "pathIds": [ "intl-entry", "home", "search", "signin" ] }, { "principleId": "support-core-task-success", "checkId": "primary-flow-completion", "confidence": "high", "method": "Direct review using evidence/search-desktop.png, evidence/product-desktop.png, evidence/cart-desktop.png", "evidence": "Search rendered results, but direct product navigation returned ERR_HTTP2_PROTOCOL_ERROR on desktop and mobile; cart captures remained an empty shell after seven seconds.", "status": "issues", "pathIds": [ "product" ], "artifacts": [ "evidence/search-desktop.png", "evidence/product-desktop.png", "evidence/cart-desktop.png" ], "findingIds": [ "F08" ] }, { "principleId": "support-core-task-success", "checkId": "clear-system-state-and-recovery", "confidence": "high", "method": "Direct review using evidence/product-desktop.png, evidence/cart-desktop.png", "evidence": "The failed product capture shows a browser protocol error and the cart capture shows only global chrome with a blank content region, no loading, empty, retry, or back-to-shopping state.", "status": "issues", "pathIds": [ "cart" ], "artifacts": [ "evidence/product-desktop.png", "evidence/cart-desktop.png" ], "findingIds": [ "F09" ] }, { "principleId": "be-fast-and-stable", "checkId": "good-core-web-vitals", "confidence": "high", "method": "Direct review using evidence/home-lighthouse.json, evidence/home-trace-summary.json, evidence/home-trace.json", "evidence": "Lighthouse measured LCP 8.9 s, TBT 3,150 ms and Speed Index 13.1 s (performance 31); the independent trace measured FCP/LCP 9.38 s.", "status": "issues", "pathIds": [ "home" ], "artifacts": [ "evidence/home-lighthouse.json", "evidence/home-trace-summary.json", "evidence/home-trace.json" ], "findingIds": [ "F10" ] }, { "principleId": "be-fast-and-stable", "checkId": "visual-stability", "confidence": "high", "method": "Direct review using evidence/us-home-mobile-layout.json", "evidence": "The mobile layout observer recorded CLS 0.186 with a largest individual shift of 0.115, above the good threshold.", "status": "issues", "pathIds": [ "home" ], "artifacts": [ "evidence/us-home-mobile-layout.json" ], "findingIds": [ "F11" ] }, { "principleId": "be-fast-and-stable", "checkId": "efficient-main-thread", "confidence": "high", "method": "Direct review using evidence/home-trace-summary.json, evidence/home-lighthouse.json", "evidence": "The trace found seven long tasks, a 659 ms longest task and 1,323 ms TBT; Lighthouse measured 3,150 ms TBT, 7.2 s JS execution and 9.9 s main-thread work.", "status": "issues", "pathIds": [ "home" ], "artifacts": [ "evidence/home-trace-summary.json", "evidence/home-lighthouse.json" ], "findingIds": [ "F12" ] }, { "principleId": "be-fast-and-stable", "checkId": "efficient-resource-delivery", "confidence": "high", "method": "Direct review using evidence/home-summary.json, evidence/home.har, evidence/home-lighthouse.json", "evidence": "HAR recorded 275 requests and 6.66 MB transferred, including ten parser-inserted VeryHigh-priority stylesheets; Lighthouse estimates 900 ms render-blocking and 844 KiB cache savings.", "status": "issues", "pathIds": [ "home" ], "artifacts": [ "evidence/home-summary.json", "evidence/home.har", "evidence/home-lighthouse.json" ], "findingIds": [ "F13" ] }, { "principleId": "be-fast-and-stable", "checkId": "trim-unused-and-duplicate-code", "confidence": "high", "method": "Direct review using evidence/home-summary.json, evidence/home-lighthouse.json", "evidence": "HAR recorded 150 scripts transferring 6.06 MB, including a 1.06 MB chunk; Lighthouse estimates 3,156 KiB unused JavaScript and 54 KiB unused CSS.", "status": "issues", "pathIds": [ "home" ], "artifacts": [ "evidence/home-summary.json", "evidence/home-lighthouse.json" ], "findingIds": [ "F14" ] }, { "principleId": "be-inclusive", "checkId": "names-roles-labels", "confidence": "high", "method": "Direct review using evidence/home-lighthouse.json, evidence/home-images.json", "evidence": "Lighthouse accessibility scored 84 and failed link-name and aria-allowed-attr; the image audit also reported 15 images without alt attributes.", "status": "issues", "pathIds": [ "home" ], "artifacts": [ "evidence/home-lighthouse.json", "evidence/home-images.json" ], "findingIds": [ "F15" ] }, { "principleId": "be-inclusive", "checkId": "sufficient-contrast", "confidence": "high", "method": "Lighthouse contrast audit plus screenshots.", "evidence": "Lighthouse did not flag color-contrast among automated accessibility audits, and visible white/blue and black/white text is legible in captures.", "status": "pass", "pathIds": [ "intl-entry", "home", "search", "signin" ] }, { "principleId": "be-inclusive", "checkId": "structure-and-focus", "confidence": "high", "method": "Direct review using evidence/us-home-recon.json, evidence/home-lighthouse.json, evidence/home-dom.json", "evidence": "The US homepage rendered no h1, Lighthouse flagged positive tabindex, and the international language buttons explicitly suppress their focus outline.", "status": "issues", "pathIds": [ "home" ], "artifacts": [ "evidence/us-home-recon.json", "evidence/home-lighthouse.json", "evidence/home-dom.json" ], "findingIds": [ "F16" ] }, { "principleId": "be-inclusive", "checkId": "legible-text", "confidence": "high", "method": "Visual review of entry, home, search and sign-in screenshots.", "evidence": "Desktop content uses readable font sizes, line lengths and hierarchy; no text clipping is visible at the supported desktop condition.", "status": "pass", "pathIds": [ "intl-entry", "home", "search", "signin" ] }, { "principleId": "be-inclusive", "checkId": "zoom-reflow-targets-and-media", "confidence": "high", "method": "Direct review using evidence/home-lighthouse.json, evidence/us-home-mobile-layout.json, evidence/home-holistic-probe.json", "evidence": "Lighthouse failed meta-viewport because user scaling is disabled or maximum-scale is below 5; mobile evidence shows 709 px overflow and 16 px-high links.", "status": "issues", "pathIds": [ "home" ], "artifacts": [ "evidence/home-lighthouse.json", "evidence/us-home-mobile-layout.json", "evidence/home-holistic-probe.json" ], "findingIds": [ "F17" ] }, { "principleId": "follow-best-practices", "checkId": "no-console-errors", "confidence": "high", "method": "Direct review using evidence/home-lighthouse.json", "evidence": "Lighthouse failed errors-in-console during the audited load.", "status": "issues", "pathIds": [ "home" ], "artifacts": [ "evidence/home-lighthouse.json" ], "findingIds": [ "F18" ] }, { "principleId": "follow-best-practices", "checkId": "sound-document-and-assets", "confidence": "high", "method": "Direct review using evidence/home-lighthouse.json, evidence/home-images.json, evidence/home-holistic-probe.json", "evidence": "Lighthouse found unsized images and two deprecated API warnings; the image audit found 17 images without responsive sources and two oversized images.", "status": "issues", "pathIds": [ "home" ], "artifacts": [ "evidence/home-lighthouse.json", "evidence/home-images.json", "evidence/home-holistic-probe.json" ], "findingIds": [ "F19" ] }, { "principleId": "follow-best-practices", "checkId": "browser-platform-hygiene", "confidence": "high", "method": "Direct review using evidence/home-lighthouse.json", "evidence": "Lighthouse found three BFCache failure reasons, missing source maps for large first-party JS, inspector issues, deprecated APIs and console errors.", "status": "issues", "pathIds": [ "home" ], "artifacts": [ "evidence/home-lighthouse.json" ], "findingIds": [ "F20" ] }, { "principleId": "be-discoverable", "checkId": "title-and-description", "confidence": "high", "method": "DOM metadata probe and Lighthouse SEO audit.", "evidence": "The homepage has a descriptive title and meta description, confirmed by DOM probes and Lighthouse.", "status": "pass", "pathIds": [ "home" ] }, { "principleId": "be-discoverable", "checkId": "crawlable-and-mobile-friendly", "confidence": "high", "method": "Direct review using evidence/home-lighthouse.json", "evidence": "Lighthouse SEO scored 85, reported an invalid robots.txt and two links without descriptive text.", "status": "issues", "pathIds": [ "home" ], "artifacts": [ "evidence/home-lighthouse.json" ], "findingIds": [ "F21" ] }, { "principleId": "be-discoverable", "checkId": "canonical-and-indexing-signals", "confidence": "high", "method": "Direct review using evidence/home-lighthouse.json, evidence/home-discoverability.json", "evidence": "The canonical URL is present, but Lighthouse reports invalid robots.txt; the raw crawler fetch also failed, preventing reliable non-JS retrieval in this run.", "status": "issues", "pathIds": [ "home" ], "artifacts": [ "evidence/home-lighthouse.json", "evidence/home-discoverability.json" ], "findingIds": [ "F22" ] }, { "principleId": "be-discoverable", "checkId": "structured-and-shareable-metadata", "confidence": "high", "method": "Direct review using evidence/home-holistic-probe.json", "evidence": "The holistic DOM probe found zero JSON-LD blocks and no og:title on a public retail homepage.", "status": "issues", "pathIds": [ "home" ], "artifacts": [ "evidence/home-holistic-probe.json" ], "findingIds": [ "F23" ] }, { "principleId": "be-private-and-secure", "checkId": "secure-transport-and-headers", "confidence": "high", "method": "Direct review using evidence/home-headers.json, evidence/home-cookies.json", "evidence": "The HTTPS document lacked CSP, HSTS, nosniff, frame protection, Referrer-Policy and Permissions-Policy; 26 cookies were flagged insecure and many used SameSite=None.", "status": "issues", "pathIds": [ "home" ], "artifacts": [ "evidence/home-headers.json", "evidence/home-cookies.json" ], "findingIds": [ "F24" ] }, { "principleId": "be-private-and-secure", "checkId": "data-minimisation-and-third-parties", "confidence": "high", "method": "Direct review using evidence/home-trackers.json, evidence/home-summary.json", "evidence": "The tracker probe found 24 third-party origins and eight known advertising trackers; HAR recorded 78 third-party requests transferring 1.26 MB.", "status": "issues", "pathIds": [ "home" ], "artifacts": [ "evidence/home-trackers.json", "evidence/home-summary.json" ], "findingIds": [ "F25" ] }, { "principleId": "be-private-and-secure", "checkId": "in-context-permissions-and-modern-auth", "confidence": "high", "method": "Homepage permission probe and sign-in DOM/source probe.", "evidence": "Notification permission remained default with no load-time prompt; sign-in uses autocomplete=\"username webauthn\" and its source contains WebAuthn/passkey support.", "status": "pass", "pathIds": [ "home", "signin" ] }, { "principleId": "be-private-and-secure", "checkId": "defensive-browser-policies", "confidence": "high", "method": "Direct review using evidence/home-headers.json", "evidence": "Header inspection found no HSTS, clickjacking protection, Referrer-Policy, Permissions-Policy or CSP/frame-ancestors.", "status": "issues", "pathIds": [ "home" ], "artifacts": [ "evidence/home-headers.json" ], "findingIds": [ "F26" ] }, { "principleId": "be-resilient", "checkId": "progressive-enhancement", "confidence": "high", "method": "Direct review using evidence/home-discoverability-rendered.png, evidence/home-discoverability-crawler.png, evidence/home-discoverability.json", "evidence": "The discoverability run produced a blank crawler screenshot and 0% raw-content coverage while the rendered view contained 170 content tokens; the raw fetch failed.", "status": "issues", "pathIds": [ "home" ], "artifacts": [ "evidence/home-discoverability-rendered.png", "evidence/home-discoverability-crawler.png", "evidence/home-discoverability.json" ], "findingIds": [ "F27" ] }, { "principleId": "be-resilient", "checkId": "resilient-runtime-behaviour", "confidence": "high", "method": "Direct review using evidence/product-desktop.png, evidence/cart-desktop.png", "evidence": "Product navigation produced ERR_HTTP2_PROTOCOL_ERROR and the cart rendered global chrome over an empty content region with no in-page fallback.", "status": "issues", "pathIds": [ "product" ], "artifacts": [ "evidence/product-desktop.png", "evidence/cart-desktop.png" ], "findingIds": [ "F28" ] }, { "principleId": "be-resilient", "checkId": "offline-and-installable", "confidence": "high", "method": "Applicability judgement from representative-path recon", "evidence": "The audited retail purchase flow depends on live price, inventory, fulfillment and payment state; an offline/installable mode is not necessary for truthful completion, while progressive enhancement is judged separately.", "status": "not-applicable", "reason": "The audited retail purchase flow depends on live price, inventory, fulfillment and payment state; an offline/installable mode is not necessary for truthful completion, while progressive enhancement is judged separately." }, { "principleId": "be-resilient", "checkId": "network-and-http-failure-states", "confidence": "high", "method": "Direct review using evidence/product-desktop.png, evidence/cart-desktop.png", "evidence": "Repeated product and cart captures exposed a browser protocol error or blank shell without Retry, Continue shopping, status copy or preserved context.", "status": "issues", "pathIds": [ "product" ], "artifacts": [ "evidence/product-desktop.png", "evidence/cart-desktop.png" ], "findingIds": [ "F29" ] }, { "principleId": "be-internationalised", "checkId": "lang-dir-and-logical-properties", "confidence": "high", "method": "Rendered DOM inspection of the international entry.", "evidence": "The entry document declares lang=\"en\" and exposes English, French and Spanish variants with language-scoped content and country routing.", "status": "pass", "pathIds": [ "intl-entry" ] }, { "principleId": "be-internationalised", "checkId": "locale-aware-data", "confidence": "high", "method": "Rendered multilingual entry DOM and screenshot.", "evidence": "The entry localizes complete headings/actions into English, French and Spanish and routes Canadian shoppers to the localized Canadian storefront.", "status": "pass", "pathIds": [ "intl-entry" ] }, { "principleId": "be-internationalised", "checkId": "time-zone-correctness", "confidence": "high", "method": "Applicability judgement from representative-path recon", "evidence": "No event scheduling, user-entered time, recurring interval or cross-zone coordination surface was present in the representative public paths.", "status": "not-applicable", "reason": "No event scheduling, user-entered time, recurring interval or cross-zone coordination surface was present in the representative public paths." }, { "principleId": "be-trustworthy", "checkId": "no-dark-patterns", "confidence": "high", "method": "Screenshot and text review across entry/home/sign-in.", "evidence": "Observed entry, offers and sign-in present direct choices, visible terms/privacy links and no confirmshaming or preselected paid commitment.", "status": "pass", "pathIds": [ "intl-entry", "home", "signin" ] }, { "principleId": "be-trustworthy", "checkId": "humane-error-handling", "confidence": "high", "method": "Active invalid-submit probe.", "evidence": "Submitting empty sign-in focuses the email input and invokes the clear native message “Please fill in this field.” after interaction.", "status": "pass", "pathIds": [ "signin" ] }, { "principleId": "be-trustworthy", "checkId": "trustworthy-input-assistance", "confidence": "high", "method": "Sign-in form DOM probe.", "evidence": "Sign-in labels the email field and uses autocomplete=\"username webauthn\"; browser and passkey assistance are enabled rather than obstructed.", "status": "pass", "pathIds": [ "signin" ] }, { "principleId": "be-trustworthy", "checkId": "safe-commercial-and-account-flows", "confidence": "high", "method": "Direct review using evidence/search-desktop.png, evidence/product-desktop.png, evidence/cart-desktop.png", "evidence": "Search results are visible but the product route failed and cart body remained blank; pricing/commitment and checkout controls therefore could not be reviewed or reversed in the primary path.", "status": "issues", "pathIds": [ "cart" ], "artifacts": [ "evidence/search-desktop.png", "evidence/product-desktop.png", "evidence/cart-desktop.png" ], "findingIds": [ "F30" ] }, { "principleId": "be-sustainable", "checkId": "optimised-assets", "confidence": "high", "method": "Direct review using evidence/home-images.json, evidence/home-lighthouse.json", "evidence": "The image audit found 17 of 25 images without srcset, two oversized assets and one below-fold image loaded eagerly; Lighthouse estimates 165 KiB image savings.", "status": "issues", "pathIds": [ "home" ], "artifacts": [ "evidence/home-images.json", "evidence/home-lighthouse.json" ], "findingIds": [ "F31" ] }, { "principleId": "be-sustainable", "checkId": "no-wasteful-work", "confidence": "high", "method": "Direct review using evidence/home-summary.json, evidence/home-trace-summary.json", "evidence": "HAR recorded 275 requests, 150 scripts and 6.66 MB; trace LCP was 9.38 s with 1.32 s TBT, while many analytics/chat endpoints remained active.", "status": "issues", "pathIds": [ "home" ], "artifacts": [ "evidence/home-summary.json", "evidence/home-trace-summary.json" ], "findingIds": [ "F32" ] }, { "principleId": "be-sustainable", "checkId": "third-party-and-media-budget", "confidence": "high", "method": "Direct review using evidence/home-summary.json, evidence/home-trackers.json", "evidence": "Third parties made 78 requests and transferred 1.26 MB; known advertising trackers included DoubleClick, Google Ads and Tag Manager.", "status": "issues", "pathIds": [ "home" ], "artifacts": [ "evidence/home-summary.json", "evidence/home-trackers.json" ], "findingIds": [ "F33" ] }, { "principleId": "be-agent-ready", "checkId": "structured-agent-capabilities", "confidence": "high", "method": "Direct review using evidence/home-lighthouse.json, evidence/home-discoverability-crawler.png", "evidence": "Lighthouse agentic-browsing scored 33 and failed accessibility-tree and llms.txt recommendations; discoverability produced a blank crawler view.", "status": "issues", "pathIds": [ "home" ], "artifacts": [ "evidence/home-lighthouse.json", "evidence/home-discoverability-crawler.png" ], "findingIds": [ "F34" ] }, { "principleId": "be-agent-ready", "checkId": "on-device-inference", "confidence": "high", "method": "Applicability judgement from representative-path recon", "evidence": "No summarisation, language-model or other inference task was exposed where on-device AI would clearly improve these retail browsing paths.", "status": "not-applicable", "reason": "No summarisation, language-model or other inference task was exposed where on-device AI would clearly improve these retail browsing paths." }, { "principleId": "be-memory-efficient", "checkId": "no-leak-under-repeated-interaction", "confidence": "high", "method": "Direct review using evidence/heap-baseline.heapsnapshot, evidence/heap-post.heapsnapshot", "evidence": "Baseline-to-post heap snapshots after ten Shop open/Escape cycles grew from 135.4 MB/2,127,297 nodes to 152.5 MB/2,333,939 nodes (12.6% bytes, 9.7% nodes). Separate page loads can add noise, so confidence is medium.", "status": "issues", "pathIds": [ "home" ], "artifacts": [ "evidence/heap-baseline.heapsnapshot", "evidence/heap-post.heapsnapshot" ], "findingIds": [ "F35" ] }, { "principleId": "be-memory-efficient", "checkId": "bounded-footprint", "confidence": "high", "method": "Direct review using evidence/heap-baseline.heapsnapshot, evidence/home-holistic-probe.json", "evidence": "The baseline heap snapshot contained 2,127,297 heap nodes and 135.4 MB self size; the independent performance probe reported about 118.6 MB used JS heap for 858 DOM elements.", "status": "issues", "pathIds": [ "home" ], "artifacts": [ "evidence/heap-baseline.heapsnapshot", "evidence/home-holistic-probe.json" ], "findingIds": [ "F36" ] }, { "principleId": "be-memory-efficient", "checkId": "no-detached-dom-or-unbounded-listeners", "confidence": "high", "method": "Direct review using evidence/heap-baseline.heapsnapshot, evidence/heap-post.heapsnapshot", "evidence": "Ten open/close cycles were followed by 206,642 additional heap nodes and 17.1 MB additional self size. Constructor-level detached-node data and listener enumeration were unavailable, so confidence is low.", "status": "issues", "pathIds": [ "home" ], "artifacts": [ "evidence/heap-baseline.heapsnapshot", "evidence/heap-post.heapsnapshot" ], "findingIds": [ "F37" ] } ], "principleOutcomes": [ { "principleId": "respect-user-preferences", "expectation": "default", "status": "issues", "findingIds": [ "F01", "F02", "F03" ] }, { "principleId": "implement-natural-interactions", "expectation": "default", "status": "pass" }, { "principleId": "provide-guided-navigation", "expectation": "default", "status": "issues", "findingIds": [ "F04" ] }, { "principleId": "maximize-content-reduce-noise", "expectation": "default", "status": "issues", "findingIds": [ "F05" ] }, { "principleId": "adapt-to-the-form-factor", "expectation": "default", "status": "issues", "findingIds": [ "F06", "F07" ] }, { "principleId": "support-core-task-success", "expectation": "default", "status": "issues", "findingIds": [ "F08", "F09" ] }, { "principleId": "be-fast-and-stable", "expectation": "default", "status": "issues", "findingIds": [ "F10", "F11", "F12", "F13", "F14" ] }, { "principleId": "be-inclusive", "expectation": "default", "status": "issues", "findingIds": [ "F15", "F16", "F17" ] }, { "principleId": "follow-best-practices", "expectation": "default", "status": "issues", "findingIds": [ "F18", "F19", "F20" ] }, { "principleId": "be-discoverable", "expectation": "default", "status": "issues", "findingIds": [ "F21", "F22", "F23" ] }, { "principleId": "be-private-and-secure", "expectation": "default", "status": "issues", "findingIds": [ "F24", "F25", "F26" ] }, { "principleId": "be-resilient", "expectation": "contextual", "status": "issues", "findingIds": [ "F27", "F28", "F29" ] }, { "principleId": "be-internationalised", "expectation": "contextual", "status": "pass" }, { "principleId": "be-trustworthy", "expectation": "default", "status": "issues", "findingIds": [ "F30" ] }, { "principleId": "be-sustainable", "expectation": "contextual", "status": "issues", "findingIds": [ "F31", "F32", "F33" ] }, { "principleId": "be-agent-ready", "expectation": "contextual", "status": "issues", "findingIds": [ "F34" ] }, { "principleId": "be-memory-efficient", "expectation": "default", "status": "issues", "findingIds": [ "F35", "F36", "F37" ] } ], "budget": { "pathCount": 7, "auditPasses": 1 }, "agent": "pi", "runId": "2026-07-20T00-30-11-366Z" }