Assume that you browse to Microsoft SQL Server 2016 Reporting Services (SSRS 2016) web portal by using Internet Explorer or Microsoft Edge, and you set the language of the web browser to a language that is different from the language of operating system. In this situation, the language setting doesn't work, and the web portal is still displayed in the same language with your operating system.
The issue was first fixed in the following cumulative update of SQL Server:
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