Yandex has introduced a new type of notifications in the Webmaster panel. It is called “Critical issue: Duplicate pages with GET parameters were found. ” The update was noticed and shared a screenshot Alexander Alaev, head of the web studio “Alaich and Co”, author of the blog alaev.info.
Some pages of the site contain duplicate content, which differs only by the GET parameters in the URL. Bypassing them, information about important pages for the site owner is transferred to the search base more slowly, which can affect the state of the site in search.
Recommendations are given to webmasters in notifications. For example, if there are duplicates in the search due to GET parameters, Yandex recommends using the Clean-param directive in robots.txt so that the robot ignores insignificant GET parameters and combines all signals from the copy pages on the main page. When the robot learns about the changes made, pages with insignificant GET parameters will disappear from the search.
A source: Telegram