Missing canonical tag
What this means
The page declares no canonical URL, so search engines choose for themselves which variant of it to index when duplicates exist.
How to fix it
Add a self-referencing canonical link pointing at the page's preferred absolute URL.
Fix effort
This check is auto-fixable: the change can be written and validated automatically, so CrawlX can open it as a pull request for review.
Authoritative source
https://developers.google.com/search/docs/crawling-indexing/consolidate-duplicate-urls
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