--- a/devtools/client/locales/en-US/inspector.properties
+++ b/devtools/client/locales/en-US/inspector.properties
@@ -6,25 +6,16 @@
 # which is available from the Web Developer sub-menu -> 'Inspect'.
 #
 # The correct localization of this file might be to keep it in
 # English, or another language commonly spoken among web developers.
 # You want to make that choice consistent across the developer tools.
 # A good criteria is the language in which you'd find the best
 # documentation on web development on the web.
 
-# LOCALIZATION NOTE (confirmNavigationAway): Used in the Inspector tool, when
-# the user tries to navigate away from a web page, to confirm the change of
-# page.
-confirmNavigationAway.message2=If you leave this page, the changes you have made will be lost.
-confirmNavigationAway.buttonLeave=Leave Page
-confirmNavigationAway.buttonLeaveAccesskey=L
-confirmNavigationAway.buttonStay=Stay on Page
-confirmNavigationAway.buttonStayAccesskey=S
-
 breadcrumbs.siblings=Siblings
 
 # LOCALIZATION NOTE (debuggerPausedWarning): Used in the Inspector tool, when
 # the user switch to the inspector when the debugger is paused.
 debuggerPausedWarning.message=Debugger is paused. Some features like mouse selection will not work.
 
 # LOCALIZATION NOTE (nodeMenu.tooltiptext)
 # This menu appears in the Infobar (on top of the highlighted node) once
@@ -294,17 +285,16 @@ inspectorCopyHTMLSubmenu.label=Copy
 # - Paste Inner HTML
 # - Paste Outer HTML
 # - Before
 # - After
 # - As First Child
 # - As Last Child
 inspectorPasteHTMLSubmenu.label=Paste
 
-
 # LOCALIZATION NOTE (inspector.searchHTML.key):
 # Key shortcut used to focus the DOM element search box on top-right corner of
 # the markup view
 inspector.searchHTML.key=CmdOrCtrl+F
 
 # LOCALIZATION NOTE (markupView.hide.key):
 # Key shortcut used to hide the selected node in the markup view.
 markupView.hide.key=h

--- a/devtools/client/locales/en-US/styleeditor.properties
+++ b/devtools/client/locales/en-US/styleeditor.properties
@@ -4,22 +4,16 @@
 
 # LOCALIZATION NOTE These strings are used inside the Style Editor.
 # LOCALIZATION NOTE The correct localization of this file might be to keep it
 # in English, or another language commonly spoken among web developers.
 # You want to make that choice consistent across the developer tools.
 # A good criteria is the language in which you'd find the best documentation
 # on web development on the web.
 
-# LOCALIZATION NOTE  (chromeWindowTitle): This is the title of the Style Editor
-# 'chrome' window. That is, the main window with the stylesheets list.
-# The argument is either the content document's title or its href if no title
-# is available.
-chromeWindowTitle=Style Editor [%S]
-
 # LOCALIZATION NOTE  (inlineStyleSheet): This is the name used for an style sheet
 # that is declared inline in the <style> element. Shown in the stylesheets list.
 # the argument is the index (order) of the containing <style> element in the
 # document.
 inlineStyleSheet=<inline style sheet #%S>
 
 # LOCALIZATION NOTE  (newStyleSheet): This is the default name for a new
 # user-created style sheet.
@@ -77,16 +71,8 @@ ToolboxStyleEditor.label=Style Editor
 # This is used as the label for the toolbox panel.
 ToolboxStyleEditor.panelLabel=Style Editor Panel
 
 # LOCALIZATION NOTE (ToolboxStyleEditor.tooltip3):
 # This string is displayed in the tooltip of the tab when the style editor is
 # displayed inside the developer tools window.
 # A keyboard shortcut for Stylesheet Editor will be shown inside the latter pair of brackets.
 ToolboxStyleEditor.tooltip3=Stylesheet Editor (CSS) (%S)
-
-# LOCALIZATION NOTE (confirmNavigationAway): Shown in a notification box when
-# the user tries to navigate away from a web page.
-confirmNavigationAway.message=If you leave this page, unsaved changes in the Style Editor will be lost.
-confirmNavigationAway.buttonLeave=Leave Page
-confirmNavigationAway.buttonLeaveAccesskey=L
-confirmNavigationAway.buttonStay=Stay on Page
-confirmNavigationAway.buttonStayAccesskey=S