diff --git a/assets/base/i18n/cs.json b/assets/base/i18n/cs.json
index 966697430..69d158421 100644
--- a/assets/base/i18n/cs.json
+++ b/assets/base/i18n/cs.json
@@ -291,6 +291,7 @@
   "custom_status.suggestions.recent_title": "Nedávné",
   "custom_status.suggestions.title": "Návrhy",
   "custom_status.suggestions.working_from_home": "Pracuji z domova",
+  "date.unknown": "Neznámé",
   "date_separator.today": "Dnes",
   "date_separator.yesterday": "Včera",
   "default_skin_tone": "Výchozí barva vzhledu",