diff --git a/toolkit/components/printing/content/printPageSetup.xul b/toolkit/components/printing/content/printPageSetup.xul
index 94197255408c..81889fae367a 100644
--- a/toolkit/components/printing/content/printPageSetup.xul
+++ b/toolkit/components/printing/content/printPageSetup.xul
@@ -48,6 +48,7 @@
 <!DOCTYPE dialog SYSTEM "chrome://global/locale/printPageSetup.dtd">
 
 <dialog xmlns="http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul"
+  id="printPageSetupDialog"
   onload="onLoad();"
   ondialogaccept="return onAccept();"
   oncancel="return onCancel();"
diff --git a/xpfe/global/resources/content/printPageSetup.xul b/xpfe/global/resources/content/printPageSetup.xul
index 1b11cef1d4a1..5447315ad502 100644
--- a/xpfe/global/resources/content/printPageSetup.xul
+++ b/xpfe/global/resources/content/printPageSetup.xul
@@ -48,6 +48,7 @@
 <!DOCTYPE dialog SYSTEM "chrome://global/locale/printPageSetup.dtd">
 
 <dialog xmlns="http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul"
+  id="printPageSetupDialog"
   onload="onLoad();"
   ondialogaccept="return onAccept();"
   oncancel="return onCancel();"