Why it matters
Scrapers need an absolute URL returning 200 image/* (not SVG), ≤ 8 MB for Facebook and ≤ 5 MB for X, or the card renders without an image.
How to fix it
Use an absolute https URL (metadataBase does this), serve PNG/JPEG/WebP, and keep the file small.
References
More seo rules
void seo reports 60 rules in this category. What search engines need from the raw response: status codes, titles and descriptions in <head>, self-referencing canonicals, one h1, crawlable links, Open Graph, icons, robots.txt and a sitemap with real dates.
hreflang-invalidhreflang uses invalid codes or relative URLshreflang-not-reciprocalhreflang set isn't self-referencing and reciprocalog-missingRequired Open Graph tags missing (og:title, og:type, og:image, og:url)og-incompleteog:description / og:site_name missing, or og:url ≠ canonicalog-image-sizeog:image is smaller than 1200×630 or far from 1.91:1og-image-metaog:image:width/height missing or wrong, or og:image:alt missingtwitter-cardtwitter:card missingfaviconNo crawlable favicon in a Google-supported format