diff --git a/chrome/locale/en-US/zotero/zotero.properties b/chrome/locale/en-US/zotero/zotero.properties
index 7981a4bcad..af92e9f8ce 100644
--- a/chrome/locale/en-US/zotero/zotero.properties
+++ b/chrome/locale/en-US/zotero/zotero.properties
@@ -1475,6 +1475,7 @@ pdfReader.double = Double
 pdfReader.themeName = Theme Name:
 pdfReader.background = Background:
 pdfReader.foreground = Foreground:
+pdfReader.focusMode = Focus Mode
 
 spellCheck.checkSpelling = Check Spelling
 spellCheck.addRemoveDictionaries = Add/Remove Dictionaries…