diff --git a/tests/wpt/metadata/MANIFEST.json b/tests/wpt/metadata/MANIFEST.json
index a235abdc2e5..a28405e1c1a 100644
--- a/tests/wpt/metadata/MANIFEST.json
+++ b/tests/wpt/metadata/MANIFEST.json
@@ -553764,7 +553764,7 @@
    "testharness"
   ],
   "cssom/CSSStyleRule.html": [
-   "b7cfe3da8454d5c64a25c440e0776c80d8c3a751",
+   "83a876458ba609b81c86354160549ab11b018d38",
    "testharness"
   ],
   "cssom/CSSStyleSheet.html": [
diff --git a/tests/wpt/metadata/cssom/CSSStyleRule.html.ini b/tests/wpt/metadata/cssom/CSSStyleRule.html.ini
index a859aec7a83..4b0ba813427 100644
--- a/tests/wpt/metadata/cssom/CSSStyleRule.html.ini
+++ b/tests/wpt/metadata/cssom/CSSStyleRule.html.ini
@@ -9,9 +9,9 @@
   [Values of CSSRule attributes]
     expected: FAIL
 
-  [Existence, writability and type of CSSStyleRule attributes]
-    expected: FAIL
-
   [Values of CSSStyleRule attributes]
     expected: FAIL
 
+  [Existence and type of CSSStyleRule attributes]
+    expected: FAIL
+
diff --git a/tests/wpt/web-platform-tests/cssom/CSSStyleRule.html b/tests/wpt/web-platform-tests/cssom/CSSStyleRule.html
index 65d6d534046..626301a9fb0 100644
--- a/tests/wpt/web-platform-tests/cssom/CSSStyleRule.html
+++ b/tests/wpt/web-platform-tests/cssom/CSSStyleRule.html
@@ -67,8 +67,24 @@
             assert_idl_attribute(rule, "selectorText");
             assert_equals(typeof rule.selectorText, "string");
             assert_idl_attribute(rule, "style");
-            assert_readonly(rule, "style");
-        }, "Existence, writability and type of CSSStyleRule attributes");
+        }, "Existence and type of CSSStyleRule attributes");
+
+        test(function() {
+            // CSSStyleRule.style has PutForwards=cssText and SameObject.
+            var initial = rule.style.cssText;
+            var style = rule.style;
+
+            rule.style = "";
+            assert_equals(rule.style.cssText, "");
+            assert_equals(rule.style, style);
+
+            rule.style = "margin: 42px;";
+            assert_equals(rule.style.margin, "42px");
+            assert_equals(rule.style, style);
+
+            rule.style = initial;
+            assert_equals(rule.style, style);
+        }, "Assigning to CSSStyleRule.style assigns to cssText; CSSStyleRule.style returns the same object");
 
         test(function() {
             assert_equals(rule.selectorText, "div");