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You also need to edit 'available-languages.properties' in locale to enable the Dashboard to pick up your new language files - e.g. add Portuguese=pt_PT. This will then create a drop down menu for the language on the login screen of the Dashboard.
The available-languages.properties file is ISO-8859-1encoded, so extended characters like ê could have issues retaining their UTF-8 presentation. Now, the file has been updated to use the Unicode escape sequence equivalent of \u00EA instead which will not get re-encoded and displays consistently as expected.
When adding your own languages to the available-languages.properties use Unicode escape sequences for characters in the extended alphabet
Now, any changes made to the 'messages*' language file with the code corresponding to the language you select when logging in will be reflected in the Dashboard. An alternative to selecting your desired language from the drop-down on the login page is to change the URL language query to match the locale e.g. change 'lang=en_GB' to 'lang=pt_PT'. Taking 'en_GB' as an example, the 'en' represents the language whilst the 'GB' represents the country - both parts are important.
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