--- a/_locales/en/messages.json	Mon Jan 21 08:22:52 2019 +0100
+++ b/_locales/en/messages.json	Mon Jan 21 15:15:59 2019 +0100
@@ -90,5 +90,13 @@
     "missingPlaceholderError": {
         "message": "Please enter a subscription URL which contains a placeholder \"%s\" for the feed URL.",
         "description": "Error message if the placholder is missing from the subscription URL template."
+    },
+    "feedPreviewTitle": {
+        "message": "Feed Preview",
+        "description": "Title of the feed preview options."
+    },
+    "feedPreviewExpandItemLabel": {
+        "message": "Expand feed entries by default",
+        "description": "Label of the checkbox for enabling feed entry expansion by default."
     }
 }