Currently there's no way to change some translation of plurals and strings for frontend and form level (management)
The language should be injected to theme|template layer in #1927584: Add support for the Twig {% trans %} tag extension →
Provide a Language::FRONTEND to separate management and frontend strings
Follow-up from #2015543: Decide on a language-aware renderable element in Twig templates →
Active
9.5
(Drupal 8 Multilingual Initiative) is the tag used by the multilingual initiative to mark core issues (and some contributed module issues). For versions other than Drupal 8, use the i18n (Internationalization) tag on issues which involve or affect multilingual / multinational support. That is preferred over Translation.
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