canonical.href.exists
- Default
- error
- Plugin
canonical
The canonical link has a non-empty href.
Why: An empty canonical link points nowhere, and usually means a template left out a value.
When off: empty canonical links pass.
<!-- ✗ Fails -->
<link rel="canonical" href="" />
<!-- ✓ Passes -->
<link rel="canonical" href="https://example.com/about/" />
References
- Google: How to specify a canonical URL: A canonical link names a URL in its
href.