show Development language again when development mode is enabled

[Findus23]

Description:

I am not sure if this broke with my changes and the weblate migration or before, but I can't see any place in getAvailableLanguages() dev is added to the list.

Review

• Functional review done
• Potential edge cases thought about (behavior of the code with strange input, with strange internal state or possible interactions with other Matomo subsystems)
• Usability review done (is anything maybe unclear or think about anything that would cause people to reach out to support)
• Security review done
• Wording review done
• Code review done
• Tests were added if useful/possible
• Reviewed for breaking changes
• Developer changelog updated if needed
• Documentation added if needed
• Existing documentation updated if needed

[justinvelluppillai]

It looks like you could otherwise leave that code as it was and just add "dev" to global config file, then that function would remove it for prod installs (though it would be incorrectly named, should be disableDevelopmentLanguageInProdEnvironment).

Is it possible it was previously just added by developers in config, and this change now means it is added automatically when you've enabled development mode? It might also need some documentation update to avoid future confusion.

[Findus23]

@justinvelluppillai You are right that seems a lot simpler (and I guess I lost that entry with #17930). So we could just add the entry for all users as it will be ignored for non-development anyway.

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[sgiehl]

I think it's actually better to only add the language in the code if development mode is enabled, rather than adding dev to the config file. Otherwise dev would be shown as configured language in the configuration screen, which might look weird in a production instance, as it's not even a valid language code.

[justinvelluppillai]

Yep seems like a good approach to me.