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Pulsebest-practices

Detected JavaScript Libraries

What This Audit Checks

This audit inventories all detectable JavaScript libraries and their versions running on your page. It identifies frameworks like React, Angular, Vue, jQuery, and other common libraries by their global signatures.

Why It Matters

Knowing which libraries your page loads helps you catch outdated dependencies with known security vulnerabilities. It also reveals redundant libraries (e.g., loading both jQuery and a full framework) that bloat your bundle size unnecessarily.

How to Fix It

  • Update outdated libraries to the latest stable version. Cross-reference detected versions against known vulnerabilities in the Snyk vulnerability database or npm audit.
  • Remove unused libraries. If a library appears in the detection list but your code does not actively use it, remove the import and its package.
  • Avoid loading multiple libraries that serve the same purpose. Pick one framework and remove the others.
  • Use tree-shaking to ensure your bundler only includes the parts of a library you actually use.
# Check for known vulnerabilities in your dependencies
npm audit

# Update a specific package
npm update react

How Pulse Tracks This

Pulse flags this audit in your Lighthouse best-practices score. When the audit fails, Pulse shows which elements triggered it so you can fix them directly.

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