Change the language interface of piwik

I run the piwik locally.

I want to change the language of interface. It is by default in English from the installation process I made.

As I checked on the online demo off piwik there is this feature.

How can I enable it to my local instance?

Piwik chooses its language based on the language preference set in the browser used to access Piwik.

If, for example, the browser is set to Italian as the preferred language, Piwik will display everything in Italian. If the browser is set to Russian, Piwik will display everything in Russian. and so on.

But if you check the live demo Matomo Forums - Tuesday, January 9, 2018 - Web Analytics Reports - Piwik in the right up corner the 3rd tab is the change language interface option.

So why not is the same in an istallation using for example a special setting or plugin?

You can change language in your User settings in Piwik (in admin)