Symptom
BoltAudit reports JS files that aren't minified — file sizes far larger than the actual logic warrants, often paired with high render-blocking time in the Lighthouse report.
Impact
- Bigger JS payload means longer download, parse, AND execute time.
- Mobile devices spend more CPU just parsing each extra KB.
- Render-blocking scripts directly push back FCP and TTI.
Manual fix
Modern build tools (webpack with TerserPlugin, esbuild, vite, parcel) minify by default in production. Themes shipping hand-written JS can use:
- Autoptimize — combines and minifies inline + linked JS.
- WP Rocket or LiteSpeed Cache — bundled JS optimization.
- Asset CleanUp Pro — selective per-page JS optimization.
Apply Fix
One-click in the dashboard for sites where a recognised optimization plugin is already installed. BoltAudit re-runs the minification step and caches the result.
What to watch for
JS minification can break code that relies on variable names (Function.prototype.toString introspection, some debug-mode logging). After applying, smoke-test critical flows (checkout, login, contact forms) in an incognito window.
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