https://support.google.com/webmasters/answer/66359?hl=en
"However, in some cases, content is deliberately duplicated across
domains in an attempt to manipulate search engine rankings or win more
traffic. Deceptive practices like this can result in a poor user
experience, when a visitor sees substantially the same content repeated
within a set of search results."
The emphasise here is on the "across domains". Read the rest of the
article and you see that duplicate content is not a serious problem of
Joomla. It is something that we should work on, but there are a lot
bigger issues than that. For example fixing the robots.txt some time ago
had a several times larger (positive) impact on SER than anything that
we have done so far to "fix" duplicate content.
Hannes
Am 17.05.2017 um 08:23 schrieb ssnobben:
>
> This is something that destroys all the work done on our sites
> and of course on GOOGLE "Duplicate Content" = you are out of our
> service.
>
>
> Google doesn't invent URL suffixes. And if you have multiple URLs
> pointing to the same content in Joomla, it normally adds a canonical
> tag for the search engines into the generated page source code. Also
> multiple URLs to the same content on a single website is NOT what
> Google defines as duplicate content.
>
>
> Can you verify that Google not treat this as "Duplicate Content" now for
> Joomla sites? Any info, links etc. Bcs *if* Google does, this would
> have huge impact of Joomla SEO SERPs.
>
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