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With the Language Macros for Confluence, you can add and edit content in different languages on the same Confluence page.
Use a specific language macro to write content in the languages supported by Confluence.
The Pagetitle macro allows you to write and display page titles in different languages.
As an administrator, you can enable or disable languages.
To check if the macro works according to plan, use the drop-down in the upper-right corner and choose another language you used on that page.
If you want to change the language of the entire Confluence interface including the main text, you'll have to change the language in your user settings.