diff --git a/Libraries/LibWeb/DOM/Element.cpp b/Libraries/LibWeb/DOM/Element.cpp
index 1b023d32555..e6f442523c4 100644
--- a/Libraries/LibWeb/DOM/Element.cpp
+++ b/Libraries/LibWeb/DOM/Element.cpp
@@ -293,24 +293,14 @@ WebIDL::ExceptionOr<QualifiedName> validate_and_extract(JS::Realm& realm, Option
     auto local_name = qualified_name;
 
     // 4. If qualifiedName contains a U+003A (:):
-    if (qualified_name.code_points().contains(':')) {
+    auto split_result = qualified_name.bytes_as_string_view().split_view(':', SplitBehavior::KeepEmpty);
+    if (split_result.size() > 1) {
         // 1. Let splitResult be the result of running strictly split given qualifiedName and U+003A (:).
-        // FIXME: Use the "strictly split" algorithm
-
-        size_t index = 0;
-        for (auto code_point : qualified_name.code_points()) {
-            if (code_point == ':')
-                break;
-            index++;
-        }
-
         // 2. Set prefix to splitResult[0].
-        auto prefix_view = qualified_name.code_points().unicode_substring_view(0, index);
-        prefix = MUST(FlyString::from_utf8(prefix_view.as_string()));
+        prefix = MUST(FlyString::from_utf8(split_result[0]));
 
         // 3. Set localName to splitResult[1].
-        auto local_name_view = qualified_name.code_points().unicode_substring_view(index + 1);
-        local_name = MUST(FlyString::from_utf8(local_name_view.as_string()));
+        local_name = MUST(FlyString::from_utf8(split_result[1]));
     }
 
     // 5. If prefix is not a valid namespace prefix, then throw an "InvalidCharacterError" DOMException.
diff --git a/Tests/LibWeb/Text/expected/wpt-import/dom/nodes/DOMImplementation-createDocument.txt b/Tests/LibWeb/Text/expected/wpt-import/dom/nodes/DOMImplementation-createDocument.txt
index a462f935424..54505871689 100644
--- a/Tests/LibWeb/Text/expected/wpt-import/dom/nodes/DOMImplementation-createDocument.txt
+++ b/Tests/LibWeb/Text/expected/wpt-import/dom/nodes/DOMImplementation-createDocument.txt
@@ -2,8 +2,7 @@ Harness status: OK
 
 Found 430 tests
 
-426 Pass
-4 Fail
+430 Pass
 Pass	DOMImplementation.createDocument(namespace, qualifiedName, doctype)
 Pass	createDocument test: null,null,null,null
 Pass	createDocument test: metadata for null,null,null
@@ -94,7 +93,7 @@ Pass	createDocument test: characterSet aliases for undefined,"foo1",null
 Pass	createDocument test: undefined,":foo",null,"INVALID_CHARACTER_ERR"
 Pass	createDocument test: undefined,"f:oo",null,"NAMESPACE_ERR"
 Pass	createDocument test: undefined,"foo:",null,"INVALID_CHARACTER_ERR"
-Fail	createDocument test: undefined,"f::oo",null,"INVALID_CHARACTER_ERR"
+Pass	createDocument test: undefined,"f::oo",null,"INVALID_CHARACTER_ERR"
 Pass	createDocument test: undefined,"xml",null,null
 Pass	createDocument test: metadata for undefined,"xml",null
 Pass	createDocument test: characterSet aliases for undefined,"xml",null
@@ -125,11 +124,11 @@ Pass	createDocument test: "http://example.com/",":foo",null,"INVALID_CHARACTER_E
 Pass	createDocument test: "http://example.com/","f:oo",null,null
 Pass	createDocument test: metadata for "http://example.com/","f:oo",null
 Pass	createDocument test: characterSet aliases for "http://example.com/","f:oo",null
-Fail	createDocument test: "http://example.com/","f:o:o",null,null
+Pass	createDocument test: "http://example.com/","f:o:o",null,null
 Pass	createDocument test: metadata for "http://example.com/","f:o:o",null
 Pass	createDocument test: characterSet aliases for "http://example.com/","f:o:o",null
 Pass	createDocument test: "http://example.com/","foo:",null,"INVALID_CHARACTER_ERR"
-Fail	createDocument test: "http://example.com/","f::oo",null,"INVALID_CHARACTER_ERR"
+Pass	createDocument test: "http://example.com/","f::oo",null,"INVALID_CHARACTER_ERR"
 Pass	createDocument test: "http://example.com/","a:0",null,"INVALID_CHARACTER_ERR"
 Pass	createDocument test: "http://example.com/","0:a",null,null
 Pass	createDocument test: metadata for "http://example.com/","0:a",null
@@ -214,7 +213,7 @@ Pass	createDocument test: characterSet aliases for "http://example.com/","XMLNS:
 Pass	createDocument test: "http://example.com/","xmlfoo:bar",null,null
 Pass	createDocument test: metadata for "http://example.com/","xmlfoo:bar",null
 Pass	createDocument test: characterSet aliases for "http://example.com/","xmlfoo:bar",null
-Fail	createDocument test: "http://example.com/","prefix::local",null,"INVALID_CHARACTER_ERR"
+Pass	createDocument test: "http://example.com/","prefix::local",null,"INVALID_CHARACTER_ERR"
 Pass	createDocument test: "http://example.com/","namespaceURI:{",null,"INVALID_CHARACTER_ERR"
 Pass	createDocument test: "http://example.com/","namespaceURI:}",null,"INVALID_CHARACTER_ERR"
 Pass	createDocument test: "http://example.com/","namespaceURI:~",null,"INVALID_CHARACTER_ERR"
diff --git a/Tests/LibWeb/Text/expected/wpt-import/dom/nodes/Document-createElementNS.txt b/Tests/LibWeb/Text/expected/wpt-import/dom/nodes/Document-createElementNS.txt
index 2b6ca6ec518..e30db6cb8b5 100644
--- a/Tests/LibWeb/Text/expected/wpt-import/dom/nodes/Document-createElementNS.txt
+++ b/Tests/LibWeb/Text/expected/wpt-import/dom/nodes/Document-createElementNS.txt
@@ -2,8 +2,7 @@ Harness status: OK
 
 Found 596 tests
 
-584 Pass
-12 Fail
+596 Pass
 Pass	createElementNS test in HTML document: null,null,null
 Pass	createElementNS test in XML document: null,null,null
 Pass	createElementNS test in XHTML document: null,null,null
@@ -145,9 +144,9 @@ Pass	createElementNS test in XHTML document: undefined,"f:oo","NAMESPACE_ERR"
 Pass	createElementNS test in HTML document: undefined,"foo:","INVALID_CHARACTER_ERR"
 Pass	createElementNS test in XML document: undefined,"foo:","INVALID_CHARACTER_ERR"
 Pass	createElementNS test in XHTML document: undefined,"foo:","INVALID_CHARACTER_ERR"
-Fail	createElementNS test in HTML document: undefined,"f::oo","INVALID_CHARACTER_ERR"
-Fail	createElementNS test in XML document: undefined,"f::oo","INVALID_CHARACTER_ERR"
-Fail	createElementNS test in XHTML document: undefined,"f::oo","INVALID_CHARACTER_ERR"
+Pass	createElementNS test in HTML document: undefined,"f::oo","INVALID_CHARACTER_ERR"
+Pass	createElementNS test in XML document: undefined,"f::oo","INVALID_CHARACTER_ERR"
+Pass	createElementNS test in XHTML document: undefined,"f::oo","INVALID_CHARACTER_ERR"
 Pass	createElementNS test in HTML document: undefined,"xml",null
 Pass	createElementNS test in XML document: undefined,"xml",null
 Pass	createElementNS test in XHTML document: undefined,"xml",null
@@ -196,15 +195,15 @@ Pass	createElementNS test in XHTML document: "http://example.com/",":foo","INVAL
 Pass	createElementNS test in HTML document: "http://example.com/","f:oo",null
 Pass	createElementNS test in XML document: "http://example.com/","f:oo",null
 Pass	createElementNS test in XHTML document: "http://example.com/","f:oo",null
-Fail	createElementNS test in HTML document: "http://example.com/","f:o:o",null
-Fail	createElementNS test in XML document: "http://example.com/","f:o:o",null
-Fail	createElementNS test in XHTML document: "http://example.com/","f:o:o",null
+Pass	createElementNS test in HTML document: "http://example.com/","f:o:o",null
+Pass	createElementNS test in XML document: "http://example.com/","f:o:o",null
+Pass	createElementNS test in XHTML document: "http://example.com/","f:o:o",null
 Pass	createElementNS test in HTML document: "http://example.com/","foo:","INVALID_CHARACTER_ERR"
 Pass	createElementNS test in XML document: "http://example.com/","foo:","INVALID_CHARACTER_ERR"
 Pass	createElementNS test in XHTML document: "http://example.com/","foo:","INVALID_CHARACTER_ERR"
-Fail	createElementNS test in HTML document: "http://example.com/","f::oo","INVALID_CHARACTER_ERR"
-Fail	createElementNS test in XML document: "http://example.com/","f::oo","INVALID_CHARACTER_ERR"
-Fail	createElementNS test in XHTML document: "http://example.com/","f::oo","INVALID_CHARACTER_ERR"
+Pass	createElementNS test in HTML document: "http://example.com/","f::oo","INVALID_CHARACTER_ERR"
+Pass	createElementNS test in XML document: "http://example.com/","f::oo","INVALID_CHARACTER_ERR"
+Pass	createElementNS test in XHTML document: "http://example.com/","f::oo","INVALID_CHARACTER_ERR"
 Pass	createElementNS test in HTML document: "http://example.com/","a:0","INVALID_CHARACTER_ERR"
 Pass	createElementNS test in XML document: "http://example.com/","a:0","INVALID_CHARACTER_ERR"
 Pass	createElementNS test in XHTML document: "http://example.com/","a:0","INVALID_CHARACTER_ERR"
@@ -301,9 +300,9 @@ Pass	createElementNS test in XHTML document: "http://example.com/","XMLNS:foo",n
 Pass	createElementNS test in HTML document: "http://example.com/","xmlfoo:bar",null
 Pass	createElementNS test in XML document: "http://example.com/","xmlfoo:bar",null
 Pass	createElementNS test in XHTML document: "http://example.com/","xmlfoo:bar",null
-Fail	createElementNS test in HTML document: "http://example.com/","prefix::local","INVALID_CHARACTER_ERR"
-Fail	createElementNS test in XML document: "http://example.com/","prefix::local","INVALID_CHARACTER_ERR"
-Fail	createElementNS test in XHTML document: "http://example.com/","prefix::local","INVALID_CHARACTER_ERR"
+Pass	createElementNS test in HTML document: "http://example.com/","prefix::local","INVALID_CHARACTER_ERR"
+Pass	createElementNS test in XML document: "http://example.com/","prefix::local","INVALID_CHARACTER_ERR"
+Pass	createElementNS test in XHTML document: "http://example.com/","prefix::local","INVALID_CHARACTER_ERR"
 Pass	createElementNS test in HTML document: "http://example.com/","namespaceURI:{","INVALID_CHARACTER_ERR"
 Pass	createElementNS test in XML document: "http://example.com/","namespaceURI:{","INVALID_CHARACTER_ERR"
 Pass	createElementNS test in XHTML document: "http://example.com/","namespaceURI:{","INVALID_CHARACTER_ERR"