diff --git a/mozilla/browser/components/prefwindow/locale/pref-debug1.dtd b/mozilla/browser/components/prefwindow/locale/pref-debug1.dtd
deleted file mode 100644
index cd2ff52c504..00000000000
--- a/mozilla/browser/components/prefwindow/locale/pref-debug1.dtd
+++ /dev/null
@@ -1,21 +0,0 @@
-<!-- extracted from content/pref-debug.xul -->
-
-<!--LOCALIZATION NOTE : FILE DONT_TRANSLATE This file should not be translated -->
-
-<!ENTITY lHeader "Events">
-<!ENTITY rHeader "Event debugging preferences">
-
-<!-- Event Debugging -->
-<!ENTITY debugEventDebugging.label "Event Debugging">
-<!ENTITY debugPaintFlashing.label "Paint Flashing (Caps-Lock toggles)">
-<!ENTITY debugPaintDumping.label "Paint Dumping">
-<!ENTITY debugInvalidateDumping.label "Invalidate Dumping">
-<!ENTITY debugEventDumping.label "Event Dumping">
-<!ENTITY debugMotionEventDumping.label "Motion Event Dumping">
-<!ENTITY debugCrossingEventDumping.label "Crossing Event Dumping">
-
-<!-- Reflow events -->
-<!ENTITY debugReflowEvents.label                 "Reflow Debugging">
-<!ENTITY debugReflowShowFrameCounts.label        "Show frame counts">
-<!ENTITY debugReflowDumpFrameCounts.label        "Dump frame counts">
-<!ENTITY debugReflowDumpFrameByFrameCounts.label "Dump frame by frame counts">
diff --git a/mozilla/browser/components/prefwindow/locale/pref-debug2.dtd b/mozilla/browser/components/prefwindow/locale/pref-debug2.dtd
deleted file mode 100644
index fffa9a23861..00000000000
--- a/mozilla/browser/components/prefwindow/locale/pref-debug2.dtd
+++ /dev/null
@@ -1,20 +0,0 @@
-<!-- extracted from content/pref-debug.xul -->
-
-<!--LOCALIZATION NOTE : FILE DONT_TRANSLATE This file should not be translated -->
-
-<!ENTITY lHeader "Networking">
-<!ENTITY rHeader "Network debugging preferences">
-
-<!-- Network-->
-<!ENTITY debugNetworking.label        "Networking">
-<!ENTITY dirFormat                    "Directory Listing Format">
-<!ENTITY raw.label                    "Raw - for debugging only">
-<!ENTITY html.label                   "HTML">
-<!ENTITY xul.label                    "XUL (tree-based)">
-<!ENTITY httpVersion.label            "HTTP Version">
-
-<!-- Cache -->
-<!ENTITY debugCache.label             "Cache">
-<!ENTITY debugDisableXULCache.label   "Disable XUL Cache">
-<!ENTITY debugEnableMemCache.label    "Enable Mem Cache">
-<!ENTITY debugEnableDiskCache.label   "Enable Disk Cache">