Favicon references resolve

A <link rel="icon" href="/favicon-32.png"> pointing at a file that does not exist returns 404 on the browser's favicon request, which in turn shows a default globe icon in the tab and logs a 404 in analytics for every page view. The missing icon is cosmetic but persistent: once a browser caches the 404 it does not retry for hours, so the fix does not show up immediately even after the file is added.

Either create the file at the referenced path or update the <link> tag to point at one that exists. For Next.js App Router the simplest fix is to drop favicon.ico directly in the app/ directory — Next.js injects the <link> tag automatically:

app/
  favicon.ico
  layout.tsx

For other frameworks, place the file under public/ or static/ and match the href exactly.

• ID: favicon-exists
• Severity: info
• What to look for: Check for favicon references in these locations: <link rel="icon" href="..."> and <link rel="shortcut icon" href="..."> in HTML/JSX/layout files, app/favicon.ico, app/icon.{png,svg,jpg,jpeg}, app/apple-icon.{png,jpg,jpeg} (Next.js conventions), static/favicon.ico (other frameworks). For each href reference, verify the file exists. For each Next.js convention path, verify the file exists (not just the directory). Count all favicon references and convention-based files, total resolved.
• Pass criteria: Every favicon <link href> resolves to a file AND if the framework is Next.js with app/ directory, at least 1 of the convention files (favicon.ico, icon.{ext}, apple-icon.{ext}) exists OR a <link rel="icon"> is present in app/layout.tsx. Report: "X favicon references inspected, Y resolved."
• Fail criteria: A <link rel="icon"> href references a file that doesn't exist on disk.
• Skip (N/A) when: No HTML/JSX layout files contain <link rel="icon"> references AND no app/favicon.*/public/favicon.*/static/favicon.* exists (project has no favicon at all — that's a pre-launch audit finding, not this one).
• Detail on fail: "1 favicon reference unresolved: <link rel='icon' href='/favicon-32.png'> in src/app/layout.tsx (file public/favicon-32.png does not exist)"
• Remediation: Either create the missing favicon file at the referenced path, or update the <link> tag to point at an existing file. For Next.js App Router, the simplest pattern is to drop a favicon.ico directly in the app/ directory and Next.js handles it automatically.