fixup! Add TorStrings module for localization

Restore the letterbox warning for 12.0

toolkit/torbutton/chrome/locale/en-US/torbutton.properties

@@ -115,3 +115,8 @@ torbutton.popup.no_newnym = Torbutton cannot safely give you a new identity. It
 # Preferences for mobile: these strings are still referenced, but we should
 # check whether this feature is still used
 torbutton.security_settings.menu.title = Security Settings
+
+# The notification that appears when maximizing the browser with letterboxing disabled
+# TODO: This string is not needed as of 12.5a5, and has a replacement in Base Browser!
+# To be removed when 12.0 will not need new updates.
+torbutton.maximize_warning = Maximizing Tor Browser can allow websites to determine your monitor size, which can be used to track you. We recommend that you leave Tor Browser windows in their original default size.