diff --git a/web/pdf_page_view.js b/web/pdf_page_view.js
index f7e7dad3d..1bb4f1bc8 100644
--- a/web/pdf_page_view.js
+++ b/web/pdf_page_view.js
@@ -806,8 +806,7 @@ class PDFPageView {
     }
 
     const ctx = canvas.getContext("2d", { alpha: false });
-    const outputScale = getOutputScale(ctx);
-    this.outputScale = outputScale;
+    const outputScale = (this.outputScale = getOutputScale());
 
     if (this.useOnlyCssZoom) {
       const actualSizeViewport = viewport.clone({
@@ -844,9 +843,9 @@ class PDFPageView {
     this.paintedViewportMap.set(canvas, viewport);
 
     // Rendering area
-    const transform = !outputScale.scaled
-      ? null
-      : [outputScale.sx, 0, 0, outputScale.sy, 0, 0];
+    const transform = outputScale.scaled
+      ? [outputScale.sx, 0, 0, outputScale.sy, 0, 0]
+      : null;
     const renderContext = {
       canvasContext: ctx,
       transform,
diff --git a/web/pdf_thumbnail_view.js b/web/pdf_thumbnail_view.js
index b2d5541fa..91895eff5 100644
--- a/web/pdf_thumbnail_view.js
+++ b/web/pdf_thumbnail_view.js
@@ -233,7 +233,7 @@ class PDFThumbnailView {
       canvas.mozOpaque = true;
     }
     const ctx = canvas.getContext("2d", { alpha: false });
-    const outputScale = getOutputScale(ctx);
+    const outputScale = getOutputScale();
 
     canvas.width = (upscaleFactor * this.canvasWidth * outputScale.sx) | 0;
     canvas.height = (upscaleFactor * this.canvasHeight * outputScale.sy) | 0;
diff --git a/web/ui_utils.js b/web/ui_utils.js
index 86b4bd907..64450b372 100644
--- a/web/ui_utils.js
+++ b/web/ui_utils.js
@@ -79,18 +79,11 @@ const AutoPrintRegExp = /\bprint\s*\(/;
 
 /**
  * Returns scale factor for the canvas. It makes sense for the HiDPI displays.
- * @returns {Object} The object with horizontal (sx) and vertical (sy)
- *                   scales. The scaled property is set to false if scaling is
- *                   not required, true otherwise.
+ * @returns {Object} The object with horizontal (sx) and vertical (sy) scales.
+ *   The scaled property is false if scaling is not required, true otherwise.
  */
-function getOutputScale(ctx) {
-  const devicePixelRatio = window.devicePixelRatio || 1;
-  const backingStoreRatio =
-    ctx.webkitBackingStorePixelRatio ||
-    ctx.mozBackingStorePixelRatio ||
-    ctx.backingStorePixelRatio ||
-    1;
-  const pixelRatio = devicePixelRatio / backingStoreRatio;
+function getOutputScale() {
+  const pixelRatio = window.devicePixelRatio || 1;
   return {
     sx: pixelRatio,
     sy: pixelRatio,