Proposal: Improve Locale Detection Logic in TranslocoLocaleService

[chaitanay94]

I’ve been working with both Transloco and TranslocoLocale, and I noticed a potential improvement in how locale is determined in TranslocoLocaleService.

Currently, the locale is derived using:

private _locale = this.defaultLocale || this.toLocale(this.translocoService.getActiveLang());

This assumes that the active language from TranslocoService (e.g., 'fr') can be reliably converted to a full locale (e.g., 'fr-FR'). However, this approach:

Ignores the user's actual browser locale (navigator.language or navigator.languages)
Doesn't account for user preferences or app-level overrides
May lead to incorrect formatting (e.g., 'fr' mapping to 'fr-FR' when the user is in Canada and expects 'fr-CA')
💡 Proposal
Enhance TranslocoLocaleService to:

1. Prefer navigator.language as the default locale if defaultLocale is not explicitly set.
2. Allow developers to provide a custom mapping or override logic via config.
3. Optionally sync locale with language changes in TranslocoService using a plugin or shared service.

🔧 Example Implementation

private browserLocale = navigator.language || this.defaultLocale;

private _locale =this.toLocale(browserLocale)

This would ensure that both translation and formatting are aligned with the user's actual environment.

Would love to hear thoughts from the maintainers and community. Happy to contribute a PR if this direction makes sense!

@shaharkazaz we would like discuss more if required.

[chaitanay94]

i have raised a pull request #861 @shaharkazaz request you to go-through the same