At this time we still don't have any way of reproducing the missing translations issue outside of FreeFlarum.
We had some suspicions about the early resolving of the
TranslatorInterface in the
FilterPosts subscriber class, but I have investigated that and can't find any issue.
The thought was that if the extension was booting before the language pack, maybe it was locking the list of translations and preventing subsequent language packs or extension to register translations.
TranslatorInterface is indeed resolved too early and we should change this, however this cannot break translations because the class managing translations is the
LocaleManager, which is not resolved early here. A problem could only happen if an extension was trying to replace the
TranslatorInterface or change the locale cache directory.
@Sanguine do you maybe have local extenders that might show the behavior I describe?