diff --git a/components/script/dom/bindings/xmlname.rs b/components/script/dom/bindings/xmlname.rs
index 12c10620dd0..b4e6aab289f 100644
--- a/components/script/dom/bindings/xmlname.rs
+++ b/components/script/dom/bindings/xmlname.rs
@@ -10,15 +10,10 @@ use html5ever::{LocalName, Namespace, Prefix};
 
 /// Validate a qualified name. See https://dom.spec.whatwg.org/#validate for details.
 pub fn validate_qualified_name(qualified_name: &str) -> ErrorResult {
+    // Step 2.
     match xml_name_type(qualified_name) {
-        XMLName::InvalidXMLName => {
-            // Step 1.
-            Err(Error::InvalidCharacter)
-        },
-        XMLName::Name => {
-            // Step 2.
-            Err(Error::Namespace)
-        },
+        XMLName::InvalidXMLName => Err(Error::InvalidCharacter),
+        XMLName::Name => Err(Error::InvalidCharacter), // see whatwg/dom#671
         XMLName::QName => Ok(()),
     }
 }
diff --git a/tests/wpt/metadata/dom/nodes/DOMImplementation-createDocument.html.ini b/tests/wpt/metadata/dom/nodes/DOMImplementation-createDocument.html.ini
index 3ed9d9e9c90..f0187591dc8 100644
--- a/tests/wpt/metadata/dom/nodes/DOMImplementation-createDocument.html.ini
+++ b/tests/wpt/metadata/dom/nodes/DOMImplementation-createDocument.html.ini
@@ -12,78 +12,12 @@
   [createDocument test: "http://example.com/","ெ:a",null,"INVALID_CHARACTER_ERR"]
     expected: FAIL
 
-  [createDocument test: null,":foo",null,"INVALID_CHARACTER_ERR"]
-    expected: FAIL
-
-  [createDocument test: null,"foo:",null,"INVALID_CHARACTER_ERR"]
-    expected: FAIL
-
-  [createDocument test: null,"f:o:o",null,"INVALID_CHARACTER_ERR"]
-    expected: FAIL
-
-  [createDocument test: null,":",null,"INVALID_CHARACTER_ERR"]
-    expected: FAIL
-
-  [createDocument test: "",":foo",null,"INVALID_CHARACTER_ERR"]
-    expected: FAIL
-
-  [createDocument test: "","foo:",null,"INVALID_CHARACTER_ERR"]
-    expected: FAIL
-
-  [createDocument test: undefined,":foo",null,"INVALID_CHARACTER_ERR"]
-    expected: FAIL
-
-  [createDocument test: undefined,"foo:",null,"INVALID_CHARACTER_ERR"]
-    expected: FAIL
-
-  [createDocument test: undefined,"f::oo",null,"INVALID_CHARACTER_ERR"]
-    expected: FAIL
-
-  [createDocument test: "http://example.com/",":foo",null,"INVALID_CHARACTER_ERR"]
-    expected: FAIL
-
-  [createDocument test: "http://example.com/","f:o:o",null,"INVALID_CHARACTER_ERR"]
-    expected: FAIL
-
-  [createDocument test: "http://example.com/","foo:",null,"INVALID_CHARACTER_ERR"]
-    expected: FAIL
-
-  [createDocument test: "http://example.com/","f::oo",null,"INVALID_CHARACTER_ERR"]
-    expected: FAIL
-
   [createDocument test: "http://example.com/","a:0",null,"INVALID_CHARACTER_ERR"]
     expected: FAIL
 
   [createDocument test: "http://example.com/","a:ெ",null,"INVALID_CHARACTER_ERR"]
     expected: FAIL
 
-  [createDocument test: "http://example.com/","prefix::local",null,"INVALID_CHARACTER_ERR"]
-    expected: FAIL
-
-  [createDocument test: "/",":foo",null,"INVALID_CHARACTER_ERR"]
-    expected: FAIL
-
-  [createDocument test: "/","foo:",null,"INVALID_CHARACTER_ERR"]
-    expected: FAIL
-
-  [createDocument test: "http://www.w3.org/XML/1998/namespace",":foo",null,"INVALID_CHARACTER_ERR"]
-    expected: FAIL
-
-  [createDocument test: "http://www.w3.org/XML/1998/namespace","foo:",null,"INVALID_CHARACTER_ERR"]
-    expected: FAIL
-
-  [createDocument test: "http://www.w3.org/2000/xmlns/",":foo",null,"INVALID_CHARACTER_ERR"]
-    expected: FAIL
-
-  [createDocument test: "http://www.w3.org/2000/xmlns/","foo:",null,"INVALID_CHARACTER_ERR"]
-    expected: FAIL
-
-  [createDocument test: "foo:",":foo",null,"INVALID_CHARACTER_ERR"]
-    expected: FAIL
-
-  [createDocument test: "foo:","foo:",null,"INVALID_CHARACTER_ERR"]
-    expected: FAIL
-
   [createDocument test: "http://example.com/","a:̀",null,"INVALID_CHARACTER_ERR"]
     expected: FAIL
 
diff --git a/tests/wpt/metadata/dom/nodes/DOMImplementation-createDocumentType.html.ini b/tests/wpt/metadata/dom/nodes/DOMImplementation-createDocumentType.html.ini
deleted file mode 100644
index 95698e97076..00000000000
--- a/tests/wpt/metadata/dom/nodes/DOMImplementation-createDocumentType.html.ini
+++ /dev/null
@@ -1,11 +0,0 @@
-[DOMImplementation-createDocumentType.html]
-  type: testharness
-  [createDocumentType(":foo", "", "") should throw INVALID_CHARACTER_ERR]
-    expected: FAIL
-
-  [createDocumentType("foo:", "", "") should throw INVALID_CHARACTER_ERR]
-    expected: FAIL
-
-  [createDocumentType("prefix::local", "", "") should throw INVALID_CHARACTER_ERR]
-    expected: FAIL
-
diff --git a/tests/wpt/metadata/dom/nodes/Document-createElementNS.html.ini b/tests/wpt/metadata/dom/nodes/Document-createElementNS.html.ini
index ffb56232172..2f94af30f30 100644
--- a/tests/wpt/metadata/dom/nodes/Document-createElementNS.html.ini
+++ b/tests/wpt/metadata/dom/nodes/Document-createElementNS.html.ini
@@ -102,123 +102,6 @@
   [createElementNS test in XML document: "foo:","foo:","NAMESPACE_ERR"]
     expected: FAIL
 
-  [createElementNS test in HTML document: null,":foo","INVALID_CHARACTER_ERR"]
-    expected: FAIL
-
-  [createElementNS test in XML document: null,":foo","INVALID_CHARACTER_ERR"]
-    expected: FAIL
-
-  [createElementNS test in XHTML document: null,":foo","INVALID_CHARACTER_ERR"]
-    expected: FAIL
-
-  [createElementNS test in HTML document: null,"foo:","INVALID_CHARACTER_ERR"]
-    expected: FAIL
-
-  [createElementNS test in XML document: null,"foo:","INVALID_CHARACTER_ERR"]
-    expected: FAIL
-
-  [createElementNS test in XHTML document: null,"foo:","INVALID_CHARACTER_ERR"]
-    expected: FAIL
-
-  [createElementNS test in HTML document: null,"f:o:o","INVALID_CHARACTER_ERR"]
-    expected: FAIL
-
-  [createElementNS test in XML document: null,"f:o:o","INVALID_CHARACTER_ERR"]
-    expected: FAIL
-
-  [createElementNS test in XHTML document: null,"f:o:o","INVALID_CHARACTER_ERR"]
-    expected: FAIL
-
-  [createElementNS test in HTML document: null,":","INVALID_CHARACTER_ERR"]
-    expected: FAIL
-
-  [createElementNS test in XML document: null,":","INVALID_CHARACTER_ERR"]
-    expected: FAIL
-
-  [createElementNS test in XHTML document: null,":","INVALID_CHARACTER_ERR"]
-    expected: FAIL
-
-  [createElementNS test in HTML document: "",":foo","INVALID_CHARACTER_ERR"]
-    expected: FAIL
-
-  [createElementNS test in XML document: "",":foo","INVALID_CHARACTER_ERR"]
-    expected: FAIL
-
-  [createElementNS test in XHTML document: "",":foo","INVALID_CHARACTER_ERR"]
-    expected: FAIL
-
-  [createElementNS test in HTML document: "","foo:","INVALID_CHARACTER_ERR"]
-    expected: FAIL
-
-  [createElementNS test in XML document: "","foo:","INVALID_CHARACTER_ERR"]
-    expected: FAIL
-
-  [createElementNS test in XHTML document: "","foo:","INVALID_CHARACTER_ERR"]
-    expected: FAIL
-
-  [createElementNS test in HTML document: undefined,":foo","INVALID_CHARACTER_ERR"]
-    expected: FAIL
-
-  [createElementNS test in XML document: undefined,":foo","INVALID_CHARACTER_ERR"]
-    expected: FAIL
-
-  [createElementNS test in XHTML document: undefined,":foo","INVALID_CHARACTER_ERR"]
-    expected: FAIL
-
-  [createElementNS test in HTML document: undefined,"foo:","INVALID_CHARACTER_ERR"]
-    expected: FAIL
-
-  [createElementNS test in XML document: undefined,"foo:","INVALID_CHARACTER_ERR"]
-    expected: FAIL
-
-  [createElementNS test in XHTML document: undefined,"foo:","INVALID_CHARACTER_ERR"]
-    expected: FAIL
-
-  [createElementNS test in HTML document: undefined,"f::oo","INVALID_CHARACTER_ERR"]
-    expected: FAIL
-
-  [createElementNS test in XML document: undefined,"f::oo","INVALID_CHARACTER_ERR"]
-    expected: FAIL
-
-  [createElementNS test in XHTML document: undefined,"f::oo","INVALID_CHARACTER_ERR"]
-    expected: FAIL
-
-  [createElementNS test in HTML document: "http://example.com/",":foo","INVALID_CHARACTER_ERR"]
-    expected: FAIL
-
-  [createElementNS test in XML document: "http://example.com/",":foo","INVALID_CHARACTER_ERR"]
-    expected: FAIL
-
-  [createElementNS test in XHTML document: "http://example.com/",":foo","INVALID_CHARACTER_ERR"]
-    expected: FAIL
-
-  [createElementNS test in HTML document: "http://example.com/","f:o:o","INVALID_CHARACTER_ERR"]
-    expected: FAIL
-
-  [createElementNS test in XML document: "http://example.com/","f:o:o","INVALID_CHARACTER_ERR"]
-    expected: FAIL
-
-  [createElementNS test in XHTML document: "http://example.com/","f:o:o","INVALID_CHARACTER_ERR"]
-    expected: FAIL
-
-  [createElementNS test in HTML document: "http://example.com/","foo:","INVALID_CHARACTER_ERR"]
-    expected: FAIL
-
-  [createElementNS test in XML document: "http://example.com/","foo:","INVALID_CHARACTER_ERR"]
-    expected: FAIL
-
-  [createElementNS test in XHTML document: "http://example.com/","foo:","INVALID_CHARACTER_ERR"]
-    expected: FAIL
-
-  [createElementNS test in HTML document: "http://example.com/","f::oo","INVALID_CHARACTER_ERR"]
-    expected: FAIL
-
-  [createElementNS test in XML document: "http://example.com/","f::oo","INVALID_CHARACTER_ERR"]
-    expected: FAIL
-
-  [createElementNS test in XHTML document: "http://example.com/","f::oo","INVALID_CHARACTER_ERR"]
-    expected: FAIL
-
   [createElementNS test in HTML document: "http://example.com/","a:0","INVALID_CHARACTER_ERR"]
     expected: FAIL
 
@@ -237,87 +120,6 @@
   [createElementNS test in XHTML document: "http://example.com/","a:ெ","INVALID_CHARACTER_ERR"]
     expected: FAIL
 
-  [createElementNS test in HTML document: "http://example.com/","prefix::local","INVALID_CHARACTER_ERR"]
-    expected: FAIL
-
-  [createElementNS test in XML document: "http://example.com/","prefix::local","INVALID_CHARACTER_ERR"]
-    expected: FAIL
-
-  [createElementNS test in XHTML document: "http://example.com/","prefix::local","INVALID_CHARACTER_ERR"]
-    expected: FAIL
-
-  [createElementNS test in HTML document: "/",":foo","INVALID_CHARACTER_ERR"]
-    expected: FAIL
-
-  [createElementNS test in XML document: "/",":foo","INVALID_CHARACTER_ERR"]
-    expected: FAIL
-
-  [createElementNS test in XHTML document: "/",":foo","INVALID_CHARACTER_ERR"]
-    expected: FAIL
-
-  [createElementNS test in HTML document: "/","foo:","INVALID_CHARACTER_ERR"]
-    expected: FAIL
-
-  [createElementNS test in XML document: "/","foo:","INVALID_CHARACTER_ERR"]
-    expected: FAIL
-
-  [createElementNS test in XHTML document: "/","foo:","INVALID_CHARACTER_ERR"]
-    expected: FAIL
-
-  [createElementNS test in HTML document: "http://www.w3.org/XML/1998/namespace",":foo","INVALID_CHARACTER_ERR"]
-    expected: FAIL
-
-  [createElementNS test in XML document: "http://www.w3.org/XML/1998/namespace",":foo","INVALID_CHARACTER_ERR"]
-    expected: FAIL
-
-  [createElementNS test in XHTML document: "http://www.w3.org/XML/1998/namespace",":foo","INVALID_CHARACTER_ERR"]
-    expected: FAIL
-
-  [createElementNS test in HTML document: "http://www.w3.org/XML/1998/namespace","foo:","INVALID_CHARACTER_ERR"]
-    expected: FAIL
-
-  [createElementNS test in XML document: "http://www.w3.org/XML/1998/namespace","foo:","INVALID_CHARACTER_ERR"]
-    expected: FAIL
-
-  [createElementNS test in XHTML document: "http://www.w3.org/XML/1998/namespace","foo:","INVALID_CHARACTER_ERR"]
-    expected: FAIL
-
-  [createElementNS test in HTML document: "http://www.w3.org/2000/xmlns/",":foo","INVALID_CHARACTER_ERR"]
-    expected: FAIL
-
-  [createElementNS test in XML document: "http://www.w3.org/2000/xmlns/",":foo","INVALID_CHARACTER_ERR"]
-    expected: FAIL
-
-  [createElementNS test in XHTML document: "http://www.w3.org/2000/xmlns/",":foo","INVALID_CHARACTER_ERR"]
-    expected: FAIL
-
-  [createElementNS test in HTML document: "http://www.w3.org/2000/xmlns/","foo:","INVALID_CHARACTER_ERR"]
-    expected: FAIL
-
-  [createElementNS test in XML document: "http://www.w3.org/2000/xmlns/","foo:","INVALID_CHARACTER_ERR"]
-    expected: FAIL
-
-  [createElementNS test in XHTML document: "http://www.w3.org/2000/xmlns/","foo:","INVALID_CHARACTER_ERR"]
-    expected: FAIL
-
-  [createElementNS test in HTML document: "foo:",":foo","INVALID_CHARACTER_ERR"]
-    expected: FAIL
-
-  [createElementNS test in XML document: "foo:",":foo","INVALID_CHARACTER_ERR"]
-    expected: FAIL
-
-  [createElementNS test in XHTML document: "foo:",":foo","INVALID_CHARACTER_ERR"]
-    expected: FAIL
-
-  [createElementNS test in HTML document: "foo:","foo:","INVALID_CHARACTER_ERR"]
-    expected: FAIL
-
-  [createElementNS test in XML document: "foo:","foo:","INVALID_CHARACTER_ERR"]
-    expected: FAIL
-
-  [createElementNS test in XHTML document: "foo:","foo:","INVALID_CHARACTER_ERR"]
-    expected: FAIL
-
   [createElementNS test in HTML document: "http://example.com/","a:̀","INVALID_CHARACTER_ERR"]
     expected: FAIL
 
diff --git a/tests/wpt/metadata/dom/nodes/attributes.html.ini b/tests/wpt/metadata/dom/nodes/attributes.html.ini
deleted file mode 100644
index b3d17b82df7..00000000000
--- a/tests/wpt/metadata/dom/nodes/attributes.html.ini
+++ /dev/null
@@ -1,6 +0,0 @@
-[attributes.html]
-  type: testharness
-  [When qualifiedName does not match the QName production, an INVALID_CHARACTER_ERR exception is to be thrown.]
-    expected: FAIL
-
-