Make scrollbars appear in engine-specific location (#28591)

diff --git a/css/css-flexbox/overflow-auto-005.html b/css/css-flexbox/overflow-auto-005.html
index 98e55a9..65b6d73 100644
--- a/css/css-flexbox/overflow-auto-005.html
+++ b/css/css-flexbox/overflow-auto-005.html
@@ -4,6 +4,7 @@
 <link rel="help" href="https://www.w3.org/TR/css-overflow-3/#propdef-overflow">
 <link rel="help" href="https://www.w3.org/TR/css-overflow-4/#classic-scrollbars">
 <link rel="match" href="reference/overflow-auto-005-ref.html">
+<meta name="fuzzy" content="0-3;0-3">
 <meta name="assert" content="This test ensures that flexbox with 'overflow: auto' is supported, including in combination with different writing-mode and flex-direction values."/>
 <style>
 .test-row {
diff --git a/css/css-flexbox/reference/overflow-auto-005-ref.html b/css/css-flexbox/reference/overflow-auto-005-ref.html
index ace792e..6336239 100644
--- a/css/css-flexbox/reference/overflow-auto-005-ref.html
+++ b/css/css-flexbox/reference/overflow-auto-005-ref.html
@@ -28,6 +28,11 @@
     height: 200px;
     background: radial-gradient(at right 60%, red, yellow, green);
 }
+
+.vertical-rl {
+  writing-mode: vertical-rl;
+}
+
 </style>
 </head>
 <body>
@@ -45,9 +50,17 @@
         testContents += "<div class='test-row'>";
 
     var containerClass = 'container ' + results[i];
+
+    // Use vertical-rl here because Firefox and WebKit put vertical scrollbars
+    // on the left in the vertical-rl test cases, and this is the easiest way to
+    // match that.
+    let maybe_vertical = "";
+    if (i > 3 && i < 8)
+      maybe_vertical = " vertical-rl";
+
     testContents +=
         "<div class='" + containerClass + "'>" +
-        "<div class='flexbox'>" +
+        "<div class='flexbox" + maybe_vertical + "'>" +
         "<div></div>" +
         "</div>" +
         "</div>";
@@ -57,6 +70,10 @@
 
 document.body.innerHTML += testContents;
 
+Array.prototype.forEach.call(document.querySelectorAll(".left"), function(element) {
+    element.firstChild.scrollLeft = -1000;
+});
+
 Array.prototype.forEach.call(document.querySelectorAll(".right"), function(element) {
     element.firstChild.scrollLeft = 1000;
 });