--- a/layout/base/tests/chrome/printpreview_helper.xul
+++ b/layout/base/tests/chrome/printpreview_helper.xul
@@ -121,31 +121,31 @@ function startTest1() {
   // after print preview, but not during it.
   window.frames[0].wrappedJSObject.counter = counter;
   window.frames[0].counterTimeout = "document.body.firstChild.nextSibling.innerHTML = ++counter + ' timers';" +
                                     "window.setTimeout(counterTimeout, 0);";
   window.frames[0].setTimeout(window.frames[0].counterTimeout, 0);
   window.frames[0].document.body.firstChild.innerHTML = "Print preview";
 
   printpreview();
-  ctx1.drawWindow(window.frames[1], 0, 0, 300, 300, "rgb(256,256,256)");
+  ctx1.drawWindow(window.frames[1], 0, 0, 400, 400, "rgb(256,256,256)");
   window.frames[0].document.body.firstChild.innerHTML = "Galley presentation";
 
   // Add some elements.
   addHTMLContent(window.frames[0].document.body.lastChild);
   // Delete them.
   window.frames[0].document.body.lastChild.innerHTML = "";
   // And readd.
   addHTMLContent(window.frames[0].document.body.lastChild);
 
   setTimeout(finalizeTest1, 1000);
 }
 
 function finalizeTest1() {
-  ctx2.drawWindow(window.frames[1], 0, 0, 300, 300, "rgb(256,256,256)");
+  ctx2.drawWindow(window.frames[1], 0, 0, 400, 400, "rgb(256,256,256)");
   exitprintpreview();
   ok(compareCanvases(), "Canvas should be the same!");
   counter = window.frames[0].counter;
   // This timeout is needed so that we can check that timers do run after
   // print preview.
   setTimeout(runTest2, 1000);
 }
 
@@ -205,23 +205,23 @@ function runTest3() {
   setTimeout(runTest4, 0)
 }
 
 function compareFormElementPrint(el1, el2, equals) {
   window.frames[0].document.body.innerHTML = el1;
   window.frames[0].document.body.firstChild.value =
     window.frames[0].document.body.firstChild.getAttribute('value');
   printpreview();
-  ctx1.drawWindow(window.frames[1], 0, 0, 300, 300, "rgb(256,256,256)");
+  ctx1.drawWindow(window.frames[1], 0, 0, 400, 400, "rgb(256,256,256)");
   exitprintpreview();
   window.frames[0].document.body.innerHTML = el2;
   window.frames[0].document.body.firstChild.value =
     window.frames[0].document.body.firstChild.getAttribute('value');
   printpreview();
-  ctx2.drawWindow(window.frames[1], 0, 0, 300, 300, "rgb(256,256,256)");
+  ctx2.drawWindow(window.frames[1], 0, 0, 400, 400, "rgb(256,256,256)");
   exitprintpreview();
   is(compareCanvases(), equals,
      "Comparing print preview didn't succeed [" + el1 + " : " + el2 + "]");
   setTimeout(runTest3, 100);
 }
 
 // This is a crash test for bug 539060.
 function runTest4() {
@@ -263,12 +263,12 @@ function runTest6end() {
 
   finish();
 }
 
 ]]></script>
 <table style="border: 1px solid black;" xmlns="http://www.w3.org/1999/xhtml">
 <tr><th>Print preview canvas 1</th><th>Print preview canvas 2</th></tr>
 <tr>
-<td><canvas height="300" width="300"></canvas></td>
-<td><canvas height="300" width="300"></canvas></td>
+<td><canvas height="400" width="400"></canvas></td>
+<td><canvas height="400" width="400"></canvas></td>
 </tr></table>
 </window>