H1 changed by JavaScript

Opportunity severity, in the JavaScript tab

Why it matters

The main heading differs between the response and the rendered DOM, so the page topic depends on rendering.

How to fix it

Render the H1 server-side.

How Crawlune finds it

Crawlune flags H1 changed by JavaScript automatically on every crawl and lists the affected URLs under the JavaScript tab, where you can filter, inspect each page and export the list to CSV. The free version crawls up to 550 URLs with every check enabled.