Install a favicon without breaking nested pages
Having an ICO on your computer does not connect it to your website. Treat installation as three separate checks: the uploaded file, the page declaration and the browser’s actual request.
Upload first, then use the exact URL
Put favicon.ico in a public location and open that URL directly. For a site installed under /tools/, the path /tools/favicon.ico differs from /favicon.ico. A leading slash starts at the hostname root; a page-relative path can resolve differently on nested pages. Choose deliberately rather than copying a path from another site.
Add one clear declaration
Place the example below inside the document head, adjusting the path to your deployment. Check the final HTML emitted by your CMS: a theme or plugin may add another icon declaration. Avoid adding increasingly many conflicting tags while trying to fix a missing file.
Test the homepage and a deeper page
In browser developer tools, inspect the requested URL, status and response. A 200 response containing an HTML fallback is not a valid icon download. Check for authentication, redirect or CSP errors; repair the specific path or allowed source instead of disabling security policy globally. Repeat on a nested page and a fresh browser profile.
<link rel="icon" href="/tools/favicon.ico" type="image/x-icon">