diff --git a/dom/base/nsGlobalWindowInner.cpp b/dom/base/nsGlobalWindowInner.cpp
index e9c040a36d1f..c7490b9b9890 100644
--- a/dom/base/nsGlobalWindowInner.cpp
+++ b/dom/base/nsGlobalWindowInner.cpp
@@ -3513,7 +3513,7 @@ double nsGlobalWindowInner::GetDevicePixelRatio(CallerType aCallerType,
     nsAutoCString origin;
     nsresult rv = this->GetPrincipal()->GetOrigin(origin);
     if (NS_FAILED(rv) || origin != "resource://pdf.js"_ns) {
-      return 1.0;
+      return 2.0;
     }
   }