diff --git a/src/_locales/en/messages.json b/src/_locales/en/messages.json
index 4ebe5f8..3d1128b 100644
--- a/src/_locales/en/messages.json
+++ b/src/_locales/en/messages.json
@@ -99,7 +99,7 @@
     "message": "Translate on modifier key pressed"
   },
   "ifOnlyTranslateWhenModifierKeyPressedCaptionLabel": {
-    "message": "Only display translation on specified modifier key pressed"
+    "message": "Only display translation on specified modifier key pressed."
   },
   "modifierKeyLabel": {
     "message": "Modifier Key"