diff --git a/mail/locales/en-US/chrome/messenger/mailPrefsOverlay.dtd b/mail/locales/en-US/chrome/messenger/mailPrefsOverlay.dtd
deleted file mode 100644
index f2648880f723..000000000000
--- a/mail/locales/en-US/chrome/messenger/mailPrefsOverlay.dtd
+++ /dev/null
@@ -1,15 +0,0 @@
-#ifdef XP_MACOSX
-<!ENTITY prefWindow.size "width: 66em; height: 47em;">
-#else
-<!ENTITY prefWindow.size "width: 56em; height: 47em;">
-#endif
-<!ENTITY prefWindow.title "Options">
-
-<!ENTITY mailonly.label "General">
-<!ENTITY viewingMessages.label "Display">
-<!ENTITY composingMessages.label "Composition">
-<!ENTITY attachments.label "Attachments">
-<!ENTITY fonts.label "Fonts">
-<!ENTITY themes.label "Themes">
-<!ENTITY extensions.label "Extensions">
-<!ENTITY advanced.label "Advanced">
diff --git a/mail/locales/jar.mn b/mail/locales/jar.mn
index 93246b0de01f..8d8d7400df46 100644
--- a/mail/locales/jar.mn
+++ b/mail/locales/jar.mn
@@ -18,7 +18,6 @@
   locale/@AB_CD@/messenger/mailTasksOverlay.dtd                         (%chrome/messenger/mailTasksOverlay.dtd)
   locale/@AB_CD@/messenger/msgAccountCentral.dtd                        (%chrome/messenger/msgAccountCentral.dtd)
   locale/@AB_CD@/messenger/SearchDialog.dtd                             (%chrome/messenger/SearchDialog.dtd)
-* locale/@AB_CD@/messenger/mailPrefsOverlay.dtd                         (%chrome/messenger/mailPrefsOverlay.dtd)
   locale/@AB_CD@/messenger/AccountManager.dtd                           (%chrome/messenger/AccountManager.dtd)
   locale/@AB_CD@/messenger/AccountWizard.dtd                            (%chrome/messenger/AccountWizard.dtd)
   locale/@AB_CD@/messenger/am-advanced.dtd                              (%chrome/messenger/am-advanced.dtd)