image.relative
Image URL is relative. Level: Warning.
When it is raised
Raised after the image has loaded, when the tag's raw value does not begin with http://, https:// or // and is not a data: URI, and the URL it resolves to is https. Examples are /img/card.png and card.png. The API resolves the value against the page's final URL, after redirects; a protocol-relative value beginning // does not raise this check.
What it does to a shared link
The API loaded the image only because it resolved the path against the page's final URL. Any reader of the tag that does not resolve it the same way gets no usable image URL.
How to fix it
- Replace the relative path with the full absolute https URL of the image.
- Apply the same change to twitter:image if it also carries a relative path.
<!-- Before -->
<meta property="og:image" content="/img/card.png">
<!-- After -->
<meta property="og:image" content="https://example.com/img/card.png">