Canonical tag
In short
A tag that says which URL should count as the main one when the same content lives at several URLs.
Example
All filtered product list URLs pointing to the main category page with a canonical tag.
Where you'll see it in AILens
The canonical points to the right URL (TEC-005) and same content on several URLs (ENT-001) controls.
A wrong canonical can drop an important page from the index. The tag is a hint; Google may pick a different URL.
Often confused with
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