diff --git a/components/script/dom/htmlstyleelement.rs b/components/script/dom/htmlstyleelement.rs
index bf4266e1875..bbce33f3d52 100644
--- a/components/script/dom/htmlstyleelement.rs
+++ b/components/script/dom/htmlstyleelement.rs
@@ -111,6 +111,7 @@ impl HTMLStyleElement {
 
         win.layout_chan().send(Msg::AddStylesheet(sheet.clone())).unwrap();
         *self.stylesheet.borrow_mut() = Some(sheet);
+        self.cssom_stylesheet.set(None);
         doc.invalidate_stylesheets();
     }
 
diff --git a/tests/wpt/metadata/MANIFEST.json b/tests/wpt/metadata/MANIFEST.json
index a7628638b6f..cc8e73994dd 100644
--- a/tests/wpt/metadata/MANIFEST.json
+++ b/tests/wpt/metadata/MANIFEST.json
@@ -553998,7 +553998,7 @@
    "testharness"
   ],
   "cssom/style-sheet-interfaces-001.html": [
-   "15509e87505d5a22d4f6dbbffcc90c24fcee642a",
+   "e77ec7de74baa901cc15a3b90d2b29125c282562",
    "testharness"
   ],
   "cssom/style-sheet-interfaces-002.html": [
diff --git a/tests/wpt/metadata/selectors/attribute-selectors/attribute-case/semantics.html.ini b/tests/wpt/metadata/selectors/attribute-selectors/attribute-case/semantics.html.ini
deleted file mode 100644
index 804d84f3514..00000000000
--- a/tests/wpt/metadata/selectors/attribute-selectors/attribute-case/semantics.html.ini
+++ /dev/null
@@ -1,29 +0,0 @@
-[semantics.html]
-  type: testharness
-  [@namespace x 'http://www.w3.org/XML/1998/namespace'; [x|lang='A' i\] <div {http://www.w3.org/XML/1998/namespace}lang="a"> in standards mode]
-    expected: FAIL
-
-  [@namespace x 'a'; [x|foo='' i\] <div {A}foo=""> in standards mode]
-    expected: FAIL
-
-  [@namespace x 'A'; [x|foo='' i\] <div {a}foo=""> in standards mode]
-    expected: FAIL
-
-  [@namespace x 'http://www.w3.org/XML/1998/namespace'; [x|lang='A' i\] <div {http://www.w3.org/XML/1998/namespace}lang="a"> in quirks mode]
-    expected: FAIL
-
-  [@namespace x 'a'; [x|foo='' i\] <div {A}foo=""> in quirks mode]
-    expected: FAIL
-
-  [@namespace x 'A'; [x|foo='' i\] <div {a}foo=""> in quirks mode]
-    expected: FAIL
-
-  [@namespace x 'http://www.w3.org/XML/1998/namespace'; [x|lang='A' i\] <div {http://www.w3.org/XML/1998/namespace}lang="a"> in XML]
-    expected: FAIL
-
-  [@namespace x 'a'; [x|foo='' i\] <div {A}foo=""> in XML]
-    expected: FAIL
-
-  [@namespace x 'A'; [x|foo='' i\] <div {a}foo=""> in XML]
-    expected: FAIL
-
diff --git a/tests/wpt/metadata/selectors/attribute-selectors/attribute-case/syntax.html.ini b/tests/wpt/metadata/selectors/attribute-selectors/attribute-case/syntax.html.ini
deleted file mode 100644
index 3b4aa0649a8..00000000000
--- a/tests/wpt/metadata/selectors/attribute-selectors/attribute-case/syntax.html.ini
+++ /dev/null
@@ -1,218 +0,0 @@
-[syntax.html]
-  type: testharness
-  [[foo='BAR'\] /* sanity check (valid) */ in standards mode]
-    expected: FAIL
-
-  [[foo='bar' i\] in standards mode]
-    expected: FAIL
-
-  [[foo='bar' I\] in standards mode]
-    expected: FAIL
-
-  [[foo=bar i\] in standards mode]
-    expected: FAIL
-
-  [[foo="bar" i\] in standards mode]
-    expected: FAIL
-
-  [[foo='bar'i\] in standards mode]
-    expected: FAIL
-
-  [[foo='bar'i \] in standards mode]
-    expected: FAIL
-
-  [[foo='bar' i \] in standards mode]
-    expected: FAIL
-
-  [[foo='bar' /**/ i\] in standards mode]
-    expected: FAIL
-
-  [[foo='bar' i /**/ \] in standards mode]
-    expected: FAIL
-
-  [[foo='bar'/**/i/**/\] in standards mode]
-    expected: FAIL
-
-  [[foo=bar/**/i\] in standards mode]
-    expected: FAIL
-
-  [[foo='bar'\ti\t\] /* \\t */ in standards mode]
-    expected: FAIL
-
-  [[foo='bar'\ni\n\] /* \\n */ in standards mode]
-    expected: FAIL
-
-  [[foo='bar'\ri\r\] /* \\r */ in standards mode]
-    expected: FAIL
-
-  [[foo='bar' \\i\] in standards mode]
-    expected: FAIL
-
-  [[foo='bar' \\69\] in standards mode]
-    expected: FAIL
-
-  [[foo~='bar' i\] in standards mode]
-    expected: FAIL
-
-  [[foo^='bar' i\] in standards mode]
-    expected: FAIL
-
-  [[foo$='bar' i\] in standards mode]
-    expected: FAIL
-
-  [[foo*='bar' i\] in standards mode]
-    expected: FAIL
-
-  [[foo|='bar' i\] in standards mode]
-    expected: FAIL
-
-  [[|foo='bar' i\] in standards mode]
-    expected: FAIL
-
-  [[*|foo='bar' i\] in standards mode]
-    expected: FAIL
-
-  [[foo='BAR'\] /* sanity check (valid) */ in quirks mode]
-    expected: FAIL
-
-  [[foo='bar' i\] in quirks mode]
-    expected: FAIL
-
-  [[foo='bar' I\] in quirks mode]
-    expected: FAIL
-
-  [[foo=bar i\] in quirks mode]
-    expected: FAIL
-
-  [[foo="bar" i\] in quirks mode]
-    expected: FAIL
-
-  [[foo='bar'i\] in quirks mode]
-    expected: FAIL
-
-  [[foo='bar'i \] in quirks mode]
-    expected: FAIL
-
-  [[foo='bar' i \] in quirks mode]
-    expected: FAIL
-
-  [[foo='bar' /**/ i\] in quirks mode]
-    expected: FAIL
-
-  [[foo='bar' i /**/ \] in quirks mode]
-    expected: FAIL
-
-  [[foo='bar'/**/i/**/\] in quirks mode]
-    expected: FAIL
-
-  [[foo=bar/**/i\] in quirks mode]
-    expected: FAIL
-
-  [[foo='bar'\ti\t\] /* \\t */ in quirks mode]
-    expected: FAIL
-
-  [[foo='bar'\ni\n\] /* \\n */ in quirks mode]
-    expected: FAIL
-
-  [[foo='bar'\ri\r\] /* \\r */ in quirks mode]
-    expected: FAIL
-
-  [[foo='bar' \\i\] in quirks mode]
-    expected: FAIL
-
-  [[foo='bar' \\69\] in quirks mode]
-    expected: FAIL
-
-  [[foo~='bar' i\] in quirks mode]
-    expected: FAIL
-
-  [[foo^='bar' i\] in quirks mode]
-    expected: FAIL
-
-  [[foo$='bar' i\] in quirks mode]
-    expected: FAIL
-
-  [[foo*='bar' i\] in quirks mode]
-    expected: FAIL
-
-  [[foo|='bar' i\] in quirks mode]
-    expected: FAIL
-
-  [[|foo='bar' i\] in quirks mode]
-    expected: FAIL
-
-  [[*|foo='bar' i\] in quirks mode]
-    expected: FAIL
-
-  [[foo='BAR'\] /* sanity check (valid) */ in XML]
-    expected: FAIL
-
-  [[foo='bar' i\] in XML]
-    expected: FAIL
-
-  [[foo='bar' I\] in XML]
-    expected: FAIL
-
-  [[foo=bar i\] in XML]
-    expected: FAIL
-
-  [[foo="bar" i\] in XML]
-    expected: FAIL
-
-  [[foo='bar'i\] in XML]
-    expected: FAIL
-
-  [[foo='bar'i \] in XML]
-    expected: FAIL
-
-  [[foo='bar' i \] in XML]
-    expected: FAIL
-
-  [[foo='bar' /**/ i\] in XML]
-    expected: FAIL
-
-  [[foo='bar' i /**/ \] in XML]
-    expected: FAIL
-
-  [[foo='bar'/**/i/**/\] in XML]
-    expected: FAIL
-
-  [[foo=bar/**/i\] in XML]
-    expected: FAIL
-
-  [[foo='bar'\ti\t\] /* \\t */ in XML]
-    expected: FAIL
-
-  [[foo='bar'\ni\n\] /* \\n */ in XML]
-    expected: FAIL
-
-  [[foo='bar'\ri\r\] /* \\r */ in XML]
-    expected: FAIL
-
-  [[foo='bar' \\i\] in XML]
-    expected: FAIL
-
-  [[foo='bar' \\69\] in XML]
-    expected: FAIL
-
-  [[foo~='bar' i\] in XML]
-    expected: FAIL
-
-  [[foo^='bar' i\] in XML]
-    expected: FAIL
-
-  [[foo$='bar' i\] in XML]
-    expected: FAIL
-
-  [[foo*='bar' i\] in XML]
-    expected: FAIL
-
-  [[foo|='bar' i\] in XML]
-    expected: FAIL
-
-  [[|foo='bar' i\] in XML]
-    expected: FAIL
-
-  [[*|foo='bar' i\] in XML]
-    expected: FAIL
-
diff --git a/tests/wpt/web-platform-tests/cssom/style-sheet-interfaces-001.html b/tests/wpt/web-platform-tests/cssom/style-sheet-interfaces-001.html
index 3f4956cb3ad..fb1fde86eff 100644
--- a/tests/wpt/web-platform-tests/cssom/style-sheet-interfaces-001.html
+++ b/tests/wpt/web-platform-tests/cssom/style-sheet-interfaces-001.html
@@ -61,6 +61,17 @@
       assert: [ "styleElement.sheet exists", "styleElement.sheet is a CSSStyleSheet",
                 "linkElement.sheet exists", "linkElement.sheet is a CSSStyleSheet"] });
 
+    test(function () {
+      var style = document.createElement("style");
+      document.querySelector("head").appendChild(style);
+      var sheet1 = style.sheet;
+      assert_equals(sheet1.cssRules.length, 0);
+      style.appendChild(document.createTextNode("a { color: green; }"));
+      assert_equals(style.sheet.cssRules.length, 1);
+    }, "sheet_property_updates",
+    { help: "https://www.w3.org/TR/cssom-1/#the-linkstyle-interface",
+      assert: "The sheet property on LinkStyle should always return the current associated style sheet." });
+
     test(function() {
         assert_own_property(styleSheet, "ownerRule");
         assert_own_property(styleSheet, "cssRules");