diff --git a/Libraries/LibWeb/HTML/Window.idl b/Libraries/LibWeb/HTML/Window.idl
index 26ba6f977fb..37c546ac635 100644
--- a/Libraries/LibWeb/HTML/Window.idl
+++ b/Libraries/LibWeb/HTML/Window.idl
@@ -50,7 +50,7 @@ interface Window : EventTarget {
// the user agent
readonly attribute Navigator navigator;
- [ImplementedAs=navigator] readonly attribute Navigator clientInformation; // legacy alias of .navigator
+ [Replaceable, ImplementedAs=navigator] readonly attribute Navigator clientInformation; // legacy alias of .navigator
// user prompts
undefined alert();
diff --git a/Tests/LibWeb/Text/expected/wpt-import/html/webappapis/system-state-and-capabilities/the-navigator-object/clientinformation.window.txt b/Tests/LibWeb/Text/expected/wpt-import/html/webappapis/system-state-and-capabilities/the-navigator-object/clientinformation.window.txt
new file mode 100644
index 00000000000..73dd68afa9f
--- /dev/null
+++ b/Tests/LibWeb/Text/expected/wpt-import/html/webappapis/system-state-and-capabilities/the-navigator-object/clientinformation.window.txt
@@ -0,0 +1,7 @@
+Harness status: OK
+
+Found 2 tests
+
+2 Pass
+Pass window.clientInformation exists and equals window.navigator
+Pass window.clientInformation is Replaceable
\ No newline at end of file
diff --git a/Tests/LibWeb/Text/input/wpt-import/html/webappapis/system-state-and-capabilities/the-navigator-object/clientinformation.window.html b/Tests/LibWeb/Text/input/wpt-import/html/webappapis/system-state-and-capabilities/the-navigator-object/clientinformation.window.html
new file mode 100644
index 00000000000..0d67d9b889f
--- /dev/null
+++ b/Tests/LibWeb/Text/input/wpt-import/html/webappapis/system-state-and-capabilities/the-navigator-object/clientinformation.window.html
@@ -0,0 +1,8 @@
+
+
+
+
+
+
+
+
diff --git a/Tests/LibWeb/Text/input/wpt-import/html/webappapis/system-state-and-capabilities/the-navigator-object/clientinformation.window.js b/Tests/LibWeb/Text/input/wpt-import/html/webappapis/system-state-and-capabilities/the-navigator-object/clientinformation.window.js
new file mode 100644
index 00000000000..197a3b13e93
--- /dev/null
+++ b/Tests/LibWeb/Text/input/wpt-import/html/webappapis/system-state-and-capabilities/the-navigator-object/clientinformation.window.js
@@ -0,0 +1,8 @@
+test(() => {
+ assert_equals(window.clientInformation, window.navigator);
+}, "window.clientInformation exists and equals window.navigator");
+
+test(() => {
+ window.clientInformation = 1;
+ assert_equals(window.clientInformation, 1);
+}, "window.clientInformation is Replaceable");