Manifest position 52 · CrUX rank bucket 1000
https://github.com
Coverage complete
Coverage-complete representative audit of six public anonymous paths. Authenticated repository editing, settings, checkout, enterprise administration, and destructive account flows were not covered because they require credentials and represent separate gated archetypes.
Attempts
1 / 3
Judged checks
58 / 58
Blocked
0
Not run
0
This report has no published overall score. Blocked and not-run checks are not passes. A coverage-complete report means every check has a judged outcome; it does not mean every check passed.
All 58 atomic check outcomes
| Principle / check | Status | Confidence | Evidence or reason |
|---|---|---|---|
respect-user-preferencesrespects-color-scheme | issues | high | Computed styles stayed dark under both emulated light and dark preferences: html background rgb(13,17,23), color-scheme dark. The screenshots confirm no system-driven light retint. F01 medium: The public homepage ignores the system light preference and remains dark. |
respect-user-preferencesrespects-reduced-motion | pass | high | Under prefers-reduced-motion: reduce the probe reported the preference active and document.getAnimations() returned no running animations. |
respect-user-preferencesrespects-contrast | pass | high | Under forced-colors: active and prefers-contrast: more, controls retained white borders/text and links became yellow on black; the screenshot remained usable. |
implement-natural-interactionsview-transitions | issues | high | Rendered DOM/CSS inspection found no view-transition integration while the sampled navigation uses full document/state swaps. F02 low: Sampled state and route changes do not expose View Transition integration. |
implement-natural-interactionsscroll-driven-animations | pass | high | The live CSS probe detected scroll-timeline or animation-timeline rules, while the reduced-motion condition had no active animation. |
implement-natural-interactionsphysical-gestures | pass | high | DOM inspection found native dialog and popover primitives and no evidence that core navigation depends on custom pointer gestures; mobile scrolling remained native and unblocked. |
provide-guided-navigationscroll-state-aware-chrome | pass | high | The live stylesheet probe detected scroll timeline styling and long-page screenshots show section progression without persistent chrome obscuring content. |
provide-guided-navigationanchored-positioning | issues | medium | The rendered DOM contains a popover, but full captured page HTML/CSS contained no anchor-name, position-anchor, or position-try usage. F03 low: Transient UI uses popover semantics but not CSS anchor positioning or fallback positions. |
provide-guided-navigationdirects-attention | pass | high | A focused skip link receives a 2px solid outline; repository tabs, descriptive links, headings, and selected states keep focus and location understandable. |
maximize-content-reduce-noiseno-intrusive-interruptions | pass | high | Homepage, repository, search, issues, and login load screenshots show core content immediately with no consent wall or content-obscuring marketing interstitial. |
maximize-content-reduce-noisesemantic-dismissible-primitives | pass | high | DOM evidence contains two native dialog elements and a native popover; login and search use native forms and labelled controls. |
maximize-content-reduce-noisereduced-chrome | pass | high | Screenshots show the homepage prioritises product content and repository pages prioritise code, README, issues, and search results rather than decorative application borders. |
adapt-to-the-form-factorresponsive-no-horizontal-scroll | pass | high | At 360x800, homepage and repository layout captures reported scrollWidth 360, clientWidth 360, viewport meta present, and zero horizontal overflow. |
adapt-to-the-form-factorcomponent-level-responsiveness | pass | high | The live CSS probe found container query rules, and the same navigation/repository surfaces reflowed from 780px to 360px without overflow. |
adapt-to-the-form-factorinput-modality-aware | pass | high | Keyboard focus on the skip link produced a visible 2px outline; mobile screenshots retained accessible navigation and controls, and Lighthouse accessibility scored 1.00. |
support-core-task-successclear-purpose-and-primary-action | pass | high | First-viewport screenshots and descriptive titles clearly identify GitHub, the repository, search, issue listing, and sign-in purposes with visible next actions. |
support-core-task-successprimary-flow-completion | pass | high | Anonymous users could traverse homepage, repository detail, issue listing, repository search results, and sign-in endpoints without a dead end or bot wall. |
support-core-task-successclear-system-state-and-recovery | pass | high | Empty required sign-in submission marked username and password invalid, exposed an alert, and the sampled 404 returned a deliberate Not Found recovery page rather than a blank shell. |
be-fast-and-stablegood-core-web-vitals | issues | high | Mobile Lighthouse measured LCP 23.2s, FCP 13.0s, CLS 0, and TBT 180ms; a separate trace measured LCP 2.16s and TBT 178ms, showing stability but poor throttled load performance. F04 high: The throttled homepage has very slow paint and LCP despite stable layout. |
be-fast-and-stablevisual-stability | pass | high | Both mobile layout captures observed CLS 0 with no recorded layout shifts; Lighthouse also measured CLS 0. |
be-fast-and-stableefficient-main-thread | pass | high | Trace total blocking time was 178ms with six long tasks and Lighthouse TBT was 180ms, within the good 200ms lab threshold despite room for improvement. |
be-fast-and-stableefficient-resource-delivery | issues | high | HAR captured 154 requests and 4,115,544 transferred bytes, including 26 stylesheets and ten parser-inserted VeryHigh-priority stylesheet candidates confirmed in the document head. F05 high: The homepage delivery chain is large and stylesheet-heavy. |
be-fast-and-stabletrim-unused-and-duplicate-code | issues | high | Lighthouse estimated 828 KiB unused JavaScript and 202 KiB unused CSS; HAR recorded 100 script requests transferring 1.92 MB. F06 high: The landing page ships substantial unused JavaScript and CSS. |
be-inclusivenames-roles-labels | issues | high | Lighthouse identified a serious accessible-name mismatch: the visible button text Code is not included in aria-label Select a GitHub feature. F07 medium: A feature selector accessible name does not include its visible label. |
be-inclusivesufficient-contrast | pass | high | Lighthouse accessibility scored 1.00 for its category checks, and forced-colors evidence showed distinct white controls and yellow links on black. |
be-inclusivestructure-and-focus | pass | high | Landmark probe found header, nav, main, and footer regions; focus on Skip to content had a visible 2px solid outline and content headings were present across sampled pages. |
be-inclusivelegible-text | pass | high | Desktop and mobile screenshots show readable body sizes, restrained line lengths, and no clipping across homepage, repository, search, issues, and sign-in. |
be-inclusivezoom-reflow-targets-and-media | pass | high | Viewport meta is present; 360px screenshots reflow without horizontal overflow, and Lighthouse accessibility scored 1.00. |
follow-best-practicesno-console-errors | pass | high | Lighthouse errors-in-console audit scored 1.00 with an empty item list. |
follow-best-practicessound-document-and-assets | issues | high | Document has HTML doctype and UTF-8 charset, but image evidence found all 24 img elements lacked both explicit dimensions and Lighthouse flagged two unsized logos. F08 medium: Homepage images frequently omit explicit intrinsic dimensions. |
follow-best-practicesbrowser-platform-hygiene | pass | high | Lighthouse confirmed BFCache eligibility, no console errors were captured, and probes found no permission prompt on load; security policy details are judged separately. |
be-discoverabletitle-and-description | pass | high | Homepage and repository DOM probes found unique descriptive titles and meta descriptions; raw HTML retained title, h1, and description. |
be-discoverablecrawlable-and-mobile-friendly | pass | high | Lighthouse SEO scored 1.00; crawlable anchors, robots.txt, link text, viewport, and crawlability audits all passed. |
be-discoverablecanonical-and-indexing-signals | pass | high | Homepage returned HTTP 200, exposed canonical https://github.com/, had no accidental noindex, and robots.txt parsed successfully in Lighthouse. |
be-discoverablestructured-and-shareable-metadata | issues | high | Homepage exposes seven accurate Open Graph fields but no JSON-LD; repository detail also exposed seven Open Graph fields and no JSON-LD for its repository entity. F09 low: Share metadata is strong, but rich entities lack JSON-LD. |
be-private-and-securesecure-transport-and-headers | pass | high | HTTPS, HSTS preload, CSP, nosniff, frame denial, secure SameSite=Lax cookies, no mixed-content signal, and zero exposed secrets were observed. |
be-private-and-securedata-minimisation-and-third-parties | pass | high | Tracker probe found no known trackers and only one asset origin; all six cookies were first-party, and collector traffic was 1.4 KB. |
be-private-and-securein-context-permissions-and-modern-auth | pass | high | No permission prompt appeared on load; sign-in exposes Continue with passkey and Sign in with a passkey plus correct username/current-password autocomplete. |
be-private-and-securedefensive-browser-policies | issues | high | Headers include HSTS, DENY/frame-ancestors, nosniff, and referrer policy, but Permissions-Policy is absent and CSP permits unsafe-inline styles. F10 medium: Permissions-Policy is absent and the CSP allows inline styles. |
be-resilientprogressive-enhancement | pass | high | Discoverability fetch returned 200 with 94% rendered-word coverage in raw HTML; title, h1, and description survive without JavaScript and crawler screenshot contains content. |
be-resilientresilient-runtime-behaviour | pass | high | Native dialog/popover semantics, successful mobile reflow, stable repository/search rendering, and BFCache eligibility provide direct robust-runtime evidence. |
be-resilientoffline-and-installable | not-applicable | high | GitHub is an intrinsically online code-hosting and collaboration service. An offline clone of the public application is not a meaningful core flow; the manifest was still inspected. |
be-resilientnetwork-and-http-failure-states | pass | high | A deliberate missing path returned HTTP 404 and a designed Not Found page; invalid sign-in showed actionable state rather than a broken shell. |
be-internationalisedlang-dir-and-logical-properties | issues | high | html lang is en and 89 logical-property rules were detected, but the same live stylesheets contained 1,425 physical left/right rules and no explicit dir, creating avoidable bidi risk. F11 medium: The stylesheet still relies heavily on physical left/right properties. |
be-internationalisedlocale-aware-data | pass | high | Issue listings use relative-time custom elements with machine-readable UTC datetime values and browser-localised human-readable title values. |
be-internationalisedtime-zone-correctness | pass | high | Twenty sampled issue timestamps used unambiguous Z-suffixed UTC datetimes and rendered titles adjusted to the browser GMT+1 zone. |
be-trustworthyno-dark-patterns | pass | high | Homepage, search, repository, issues, and sign-in screenshots show honest action labels, visible sign-in boundaries, no consent nag, and no disguised advertising. |
be-trustworthyhumane-error-handling | pass | high | Empty sign-in submission uses required fields, browser invalid state, labels, and a live alert; users can correct the fields without losing context. |
be-trustworthytrustworthy-input-assistance | pass | high | Sign-in fields are explicitly labelled and use autocomplete=username and autocomplete=current-password; passkey alternatives are visible. |
be-trustworthysafe-commercial-and-account-flows | pass | high | The sampled account entry point clearly distinguishes sign-in and passkey options with labelled credentials and no forced continuity or hidden commitment. |
be-sustainableoptimised-assets | issues | high | Image audit found three oversized PNGs, 13 images without srcset, three legacy-format images, and 24 without both dimension attributes. F12 medium: Several images are oversized or lack responsive source selection. |
be-sustainableno-wasteful-work | issues | high | HAR recorded 4.12 MB including four decorative GLB fetches totalling about 827 KB, while Lighthouse found 828 KiB unused JavaScript and 202 KiB unused CSS. F13 high: The homepage fetches optional 3D assets and large unused bundles before user demand. |
be-sustainablethird-party-and-media-budget | issues | high | The homepage made 154 requests and transferred 4.12 MB, including 1.92 MB scripts, a 220 KB font, 583 KB images, and 826 KB XHR/3D assets for a marketing entry page. F14 high: A 4.12 MB, 154-request landing page is disproportionate to its initial task. |
be-agent-readystructured-agent-capabilities | issues | medium | The raw page is highly machine-readable and links to an MCP Registry, but captured DOM and scripts exposed no WebMCP or browser-registered agent tools for search, repository, or sign-in capabilities. F15 low: GitHub promotes MCP but its sampled web UI does not expose browser-native structured tools. |
be-agent-readyon-device-inference | not-applicable | medium | No sampled public GitHub flow has a task that should clearly use browser-provided on-device inference instead of GitHub server capabilities. |
be-memory-efficientno-leak-under-repeated-interaction | pass | high | After ten repeated native disclosure open/close cycles, retained self size rose only 312,619 bytes (0.5%) and node count 1,140 (0.1%), with no growing Detached constructor in summaries. |
be-memory-efficientbounded-footprint | issues | high | A single homepage state retained 1,003,253 heap nodes, 3,534,921 edges, and 62.1 MB self size, disproportionate for a public marketing page. F16 medium: The anonymous marketing homepage has a large initial heap and DOM-related footprint. |
be-memory-efficientno-detached-dom-or-unbounded-listeners | pass | high | Baseline/post heap summaries showed no Detached constructor among top populations; object and closure counts changed only slightly after ten cycles. |
Provenance
Canonical report: results/atomic/reports/0052-github_com.json
Report SHA-256: 8b3a5c0627f2b641e080da4985164f8d8503f47ca8813877835fc2a90340c434
Local retained report: runs/2026-07-17T17-27-24-856Z/atomic-reports/github_com/2026-07-18T02-28-38-507Z/report.json
Local evidence root: runs/2026-07-17T17-27-24-856Z/atomic-reports/github_com/2026-07-18T02-28-38-507Z
Catalog SHA-256: sha256:78ccfdb2d483f4c57d9dafed80fd86c6265585a56457c8dcfddc254b80fb44d7
Raw screenshots, HARs, traces, heaps, and other browser artifacts are retained at the local evidence root and intentionally are not committed. Artifact paths in the canonical report are relative to that root.