* Lazy load i18n translations.
* Lazy load date-fns
* Fix inconsistent DOMContentLoaded event.
Only when no translations and date-fns have to be dynamically loaded
(e.g. for en-US) the NavBar `componentDidMount` is early enough to
listen for "DOMContentLoaded".
Removes one redundant `requestNotificationPermission()` call.
* Rename interface language code "pt_BR" to "pt-BR".
Browsers ask for "pt-BR", but the "interface_language" saved in the
settings dialog asks for "pt_BR". This change will make the settings
dialog ask for "pt-BR" instead of "pt_BR". For users that already (or
still) have "pt_BR" configured, "pt-BR" will be used, but the settings
dialog will present it as unspecified.
* Use Accept-Language request header
* Prefetch translation and date-fns
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Co-authored-by: SleeplessOne1917 <28871516+SleeplessOne1917@users.noreply.github.com>