Issue Summary

A Jira user can encounter an odd behavior with Jira's language configuration, where non-installed language options, i.e. as "Deutsch (Brasilien)," appears under System>Internationalization, when specific JVM flags are set (-Duser.country=BR and -Duser.language=de ).

This behavior contradicts the system description that states only installed languages should be shown:

Steps to Reproduce

1. Install a Jira DC instance and take note od the OS language (Locale).
   • External reference for Windows: https://www.dell.com/support/kbdoc/en-us/000111205/how-to-localize-a-language-on-windows-server-2019
   • External reference for Linux: https://wiki.archlinux.org/title/Locale
2. Configure the following JVM options -Duser.country=BR -Duser.language=de and restart the Jira instance to make the changes effective.
   • Use this document as reference, the method used will depend on the OS and installation type used: https://confluence.atlassian.com/adminjiraserver/setting-properties-and-options-on-startup-938847831.html
3. Go to JIRA Administration (⚙︎) > System and edit the General configuration by clicking on Edit settings
   • You will see the option Deutsch (Brasilien), select it
4. The system language should be the same as the System locale

Expected Results

Jira should list the languages of the installed packages only.

Actual Results

Jira lists all locales that Java recognizes. However, if you select the recognized locale introduced with the JVM flags, it will default to the underlaying OS locale.

Workaround

Select those languages that have a valid installed language package.