--- a/toolkit/components/printing/content/printPreviewToolbar.js
+++ b/toolkit/components/printing/content/printPreviewToolbar.js
@@ -80,17 +80,17 @@ customElements.define("printpreview-tool
     this.mPageTextBox = document.getElementById("print-preview-pageNumber");
 
     this.mNavigateNextButton = document.getElementById("print-preview-navigateNext");
 
     this.mNavigateEndButton = document.getElementById("print-preview-navigateEnd");
 
     this.mTotalPages = document.getElementById("print-preview-totalPages");
 
-    this.mScaleCombobox = document.getElementById("print-preview-scale-label");
+    this.mScaleCombobox = document.getElementById("print-preview-scale");
 
     this.mPortaitButton = document.getElementById("print-preview-portrait-button");
 
     this.mLandscapeButton = document.getElementById("print-preview-landscape-button");
 
     this.mSimplifyPageCheckbox = document.getElementById("print-preview-simplify");
 
     this.mSimplifyPageNotAllowed = this.mSimplifyPageCheckbox.disabled;