Open Graph tags (og:title, og:description, og:image, og:url and og:type) control the preview card when a page is shared on Facebook, LinkedIn and other networks. Audit tools report pages where some of them are missing.
Why Joomla sites get it
Joomla core writes no Open Graph tags, so they come from your template or an extension, and some only write a few of them. The one most often missing is og:image: articles without an intro or full-text image have nothing to use, so their shares have no picture.
Fix it by hand
- Use an extension or template that writes the full set of tags on article pages.
- Give each article an intro or full-text image (the Images and Links tab), or set a site-wide default share image for articles without one.
Fix it with MetaGen
MetaGen writes the full set of Open Graph tags on article pages. For the image it uses the article’s full-text image, then its intro image, then the first image in the text, and finally the Default share image set in the MetaGen content plugin — so every page has one. The Open Graph tags row reminds you until a default image is set. If you use Cassiopeia Themer, its Identity screen can make a share image in your brand and hand it to MetaGen.
MetaGen is free for Joomla 5 and 6. See all the SEO warnings MetaGen checks.
