Webpage JavaScript Error Checker
Loads the page in a real browser and reports any JavaScript errors thrown.
Runs a real Chromium page load — usually takes 5–15 seconds.
What this tool checks
No JavaScript errors on load
Reports uncaught JavaScript errors and console errors captured while rendering the page.
Why it matters: Script errors can break interactive features, tracking and content that is injected by JavaScript — which search engines may then not see.
If it fails: Investigate and fix the reported errors; test the page with a real browser console open.
Source: developer.chrome.com/docs/devtools/console/understand-messages
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