diff --git a/Libraries/LibWeb/CMakeLists.txt b/Libraries/LibWeb/CMakeLists.txt
index 64b0e557c48..8dd32119fac 100644
--- a/Libraries/LibWeb/CMakeLists.txt
+++ b/Libraries/LibWeb/CMakeLists.txt
@@ -314,6 +314,7 @@ set(SOURCES
     HTML/AudioTrack.cpp
     HTML/AudioTrackList.cpp
     HTML/AutocompleteElement.cpp
+    HTML/BarProp.cpp
     HTML/BeforeUnloadEvent.cpp
     HTML/BroadcastChannel.cpp
     HTML/BrowsingContext.cpp
diff --git a/Libraries/LibWeb/Forward.h b/Libraries/LibWeb/Forward.h
index f25a6cf5a4c..5481b19c46c 100644
--- a/Libraries/LibWeb/Forward.h
+++ b/Libraries/LibWeb/Forward.h
@@ -417,6 +417,7 @@ namespace Web::HTML {
 class AnimationFrameCallbackDriver;
 class AudioTrack;
 class AudioTrackList;
+class BarProp;
 class BeforeUnloadEvent;
 class BroadcastChannel;
 class BrowsingContext;
diff --git a/Libraries/LibWeb/HTML/BarProp.cpp b/Libraries/LibWeb/HTML/BarProp.cpp
new file mode 100644
index 00000000000..ee7657c5cb0
--- /dev/null
+++ b/Libraries/LibWeb/HTML/BarProp.cpp
@@ -0,0 +1,47 @@
+/*
+ * Copyright (c) 2025, the Ladybird developers.
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+
+#include <LibJS/Runtime/Realm.h>
+#include <LibWeb/Bindings/BarPropPrototype.h>
+#include <LibWeb/HTML/BarProp.h>
+#include <LibWeb/HTML/Window.h>
+
+namespace Web::HTML {
+
+GC_DEFINE_ALLOCATOR(BarProp);
+
+GC::Ref<BarProp> BarProp::create(JS::Realm& realm)
+{
+    return realm.create<BarProp>(realm);
+}
+
+BarProp::BarProp(JS::Realm& realm)
+    : Bindings::PlatformObject(realm)
+{
+}
+
+// https://html.spec.whatwg.org/multipage/nav-history-apis.html#dom-barprop-visible
+bool BarProp::visible() const
+{
+    // 1. Let browsingContext be this's relevant global object's browsing context.
+    auto& global_object = HTML::relevant_global_object(*this);
+    auto* browsing_context = as<HTML::Window>(global_object).associated_document().browsing_context();
+
+    // 2. If browsingContext is null, then return true.
+    if (!browsing_context) {
+        return true;
+    }
+
+    // 3. Return the negation of browsingContext's top-level browsing context's is popup.
+    return browsing_context->top_level_browsing_context()->is_popup() != TokenizedFeature::Popup::Yes;
+}
+
+void BarProp::initialize(JS::Realm& realm)
+{
+    Base::initialize(realm);
+    WEB_SET_PROTOTYPE_FOR_INTERFACE(BarProp);
+}
+}
diff --git a/Libraries/LibWeb/HTML/BarProp.h b/Libraries/LibWeb/HTML/BarProp.h
new file mode 100644
index 00000000000..d3b0a47778d
--- /dev/null
+++ b/Libraries/LibWeb/HTML/BarProp.h
@@ -0,0 +1,30 @@
+/*
+ * Copyright (c) 2025, the Ladybird developers.
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+
+#pragma once
+
+#include <LibGC/CellAllocator.h>
+#include <LibWeb/Bindings/PlatformObject.h>
+#include <LibWeb/Forward.h>
+#include <LibWeb/WebIDL/Types.h>
+
+namespace Web::HTML {
+
+// https://html.spec.whatwg.org/multipage/nav-history-apis.html#barprop
+class BarProp : public Bindings::PlatformObject {
+    WEB_PLATFORM_OBJECT(BarProp, Bindings::PlatformObject);
+    GC_DECLARE_ALLOCATOR(BarProp);
+
+public:
+    BarProp(JS::Realm&);
+    static GC::Ref<BarProp> create(JS::Realm&);
+
+    [[nodiscard]] bool visible() const;
+
+private:
+    virtual void initialize(JS::Realm&) override;
+};
+}
diff --git a/Libraries/LibWeb/HTML/BarProp.idl b/Libraries/LibWeb/HTML/BarProp.idl
new file mode 100644
index 00000000000..2143bae3091
--- /dev/null
+++ b/Libraries/LibWeb/HTML/BarProp.idl
@@ -0,0 +1,6 @@
+
+// https://html.spec.whatwg.org/multipage/nav-history-apis.html#barprop
+[Exposed=Window]
+interface BarProp {
+    readonly attribute boolean visible;
+};
diff --git a/Libraries/LibWeb/HTML/BrowsingContext.h b/Libraries/LibWeb/HTML/BrowsingContext.h
index d0f5bf30256..466de1f3aa3 100644
--- a/Libraries/LibWeb/HTML/BrowsingContext.h
+++ b/Libraries/LibWeb/HTML/BrowsingContext.h
@@ -77,6 +77,7 @@ public:
     void set_opener_browsing_context(GC::Ptr<BrowsingContext> browsing_context) { m_opener_browsing_context = browsing_context; }
 
     void set_is_popup(TokenizedFeature::Popup is_popup) { m_is_popup = is_popup; }
+    [[nodiscard]] TokenizedFeature::Popup is_popup() const { return m_is_popup; }
 
     SandboxingFlagSet popup_sandboxing_flag_set() const { return m_popup_sandboxing_flag_set; }
     void set_popup_sandboxing_flag_set(SandboxingFlagSet value) { m_popup_sandboxing_flag_set = value; }
diff --git a/Libraries/LibWeb/HTML/Window.cpp b/Libraries/LibWeb/HTML/Window.cpp
index 646f5d6981a..a665b2dbbdf 100644
--- a/Libraries/LibWeb/HTML/Window.cpp
+++ b/Libraries/LibWeb/HTML/Window.cpp
@@ -128,6 +128,12 @@ void Window::visit_edges(JS::Cell::Visitor& visitor)
     visitor.visit(m_pdf_viewer_plugin_objects);
     visitor.visit(m_pdf_viewer_mime_type_objects);
     visitor.visit(m_close_watcher_manager);
+    visitor.visit(m_locationbar);
+    visitor.visit(m_menubar);
+    visitor.visit(m_personalbar);
+    visitor.visit(m_scrollbars);
+    visitor.visit(m_statusbar);
+    visitor.visit(m_toolbar);
 }
 
 void Window::finalize()
@@ -920,6 +926,60 @@ void Window::blur()
     // The blur() method steps are to do nothing.
 }
 
+// https://html.spec.whatwg.org/multipage/nav-history-apis.html#dom-window-locationbar
+GC::Ref<BarProp const> Window::locationbar()
+{
+    if (!m_locationbar)
+        m_locationbar = BarProp::create(realm());
+
+    return *m_locationbar;
+}
+
+// https://html.spec.whatwg.org/multipage/nav-history-apis.html#dom-window-menubar
+GC::Ref<BarProp const> Window::menubar()
+{
+    if (!m_menubar)
+        m_menubar = BarProp::create(realm());
+
+    return *m_menubar;
+}
+
+// https://html.spec.whatwg.org/multipage/nav-history-apis.html#dom-window-personalbar
+GC::Ref<BarProp const> Window::personalbar()
+{
+    if (!m_personalbar)
+        m_personalbar = BarProp::create(realm());
+
+    return *m_personalbar;
+}
+
+// https://html.spec.whatwg.org/multipage/nav-history-apis.html#dom-window-scrollbars
+GC::Ref<BarProp const> Window::scrollbars()
+{
+    if (!m_scrollbars)
+        m_scrollbars = BarProp::create(realm());
+
+    return *m_scrollbars;
+}
+
+// https://html.spec.whatwg.org/multipage/nav-history-apis.html#dom-window-statusbar
+GC::Ref<BarProp const> Window::statusbar()
+{
+    if (!m_statusbar)
+        m_statusbar = BarProp::create(realm());
+
+    return *m_statusbar;
+}
+
+// https://html.spec.whatwg.org/multipage/nav-history-apis.html#dom-window-toolbar
+GC::Ref<BarProp const> Window::toolbar()
+{
+    if (!m_toolbar)
+        m_toolbar = BarProp::create(realm());
+
+    return *m_toolbar;
+}
+
 // https://html.spec.whatwg.org/multipage/window-object.html#dom-frames
 GC::Ref<WindowProxy> Window::frames() const
 {
diff --git a/Libraries/LibWeb/HTML/Window.h b/Libraries/LibWeb/HTML/Window.h
index 4a8645973c0..7b427d03443 100644
--- a/Libraries/LibWeb/HTML/Window.h
+++ b/Libraries/LibWeb/HTML/Window.h
@@ -16,6 +16,7 @@
 #include <LibWeb/Bindings/WindowGlobalMixin.h>
 #include <LibWeb/DOM/EventTarget.h>
 #include <LibWeb/Forward.h>
+#include <LibWeb/HTML/BarProp.h>
 #include <LibWeb/HTML/CrossOrigin/CrossOriginPropertyDescriptorMap.h>
 #include <LibWeb/HTML/GlobalEventHandlers.h>
 #include <LibWeb/HTML/MimeType.h>
@@ -173,6 +174,15 @@ public:
     void focus();
     void blur();
 
+    // For historical reasons, the Window interface had some properties that represented the visibility of certain web browser interface elements.
+    // For privacy and interoperability reasons, those properties now return values that represent whether the Window's browsing context's is popup property is true or false.
+    GC::Ref<BarProp const> locationbar();
+    GC::Ref<BarProp const> menubar();
+    GC::Ref<BarProp const> personalbar();
+    GC::Ref<BarProp const> scrollbars();
+    GC::Ref<BarProp const> statusbar();
+    GC::Ref<BarProp const> toolbar();
+
     GC::Ref<WindowProxy> frames() const;
     u32 length();
     GC::Ptr<WindowProxy const> top() const;
@@ -332,6 +342,13 @@ private:
     // https://html.spec.whatwg.org/multipage/nav-history-apis.html#dom-window-status
     // When the Window object is created, the attribute must be set to the empty string. It does not do anything else.
     String m_status;
+
+    GC::Ptr<BarProp const> m_locationbar;
+    GC::Ptr<BarProp const> m_menubar;
+    GC::Ptr<BarProp const> m_personalbar;
+    GC::Ptr<BarProp const> m_scrollbars;
+    GC::Ptr<BarProp const> m_statusbar;
+    GC::Ptr<BarProp const> m_toolbar;
 };
 
 void run_animation_frame_callbacks(DOM::Document&, double now);
diff --git a/Libraries/LibWeb/HTML/Window.idl b/Libraries/LibWeb/HTML/Window.idl
index 37c546ac635..cd1e11585ab 100644
--- a/Libraries/LibWeb/HTML/Window.idl
+++ b/Libraries/LibWeb/HTML/Window.idl
@@ -34,6 +34,13 @@ interface Window : EventTarget {
     undefined focus();
     undefined blur();
 
+    [Replaceable] readonly attribute BarProp locationbar;
+    [Replaceable] readonly attribute BarProp menubar;
+    [Replaceable] readonly attribute BarProp personalbar;
+    [Replaceable] readonly attribute BarProp scrollbars;
+    [Replaceable] readonly attribute BarProp statusbar;
+    [Replaceable] readonly attribute BarProp toolbar;
+
     // other browsing contexts
     [Replaceable] readonly attribute WindowProxy frames;
     [Replaceable] readonly attribute unsigned long length;
diff --git a/Libraries/LibWeb/idl_files.cmake b/Libraries/LibWeb/idl_files.cmake
index 54d1da8b7fb..6d6af4e6a62 100644
--- a/Libraries/LibWeb/idl_files.cmake
+++ b/Libraries/LibWeb/idl_files.cmake
@@ -110,6 +110,7 @@ libweb_js_bindings(Geometry/DOMRectList)
 libweb_js_bindings(Geometry/DOMRectReadOnly)
 libweb_js_bindings(HTML/AudioTrack)
 libweb_js_bindings(HTML/AudioTrackList)
+libweb_js_bindings(HTML/BarProp)
 libweb_js_bindings(HTML/BeforeUnloadEvent)
 libweb_js_bindings(HTML/BroadcastChannel)
 libweb_js_bindings(HTML/CanvasGradient)
diff --git a/Tests/LibWeb/Text/expected/HTML/window-barprops.txt b/Tests/LibWeb/Text/expected/HTML/window-barprops.txt
new file mode 100644
index 00000000000..1255fc75307
--- /dev/null
+++ b/Tests/LibWeb/Text/expected/HTML/window-barprops.txt
@@ -0,0 +1,6 @@
+locationbar is BarProp: true visible: true
+menubar is BarProp: true visible: true
+personalbar is BarProp: true visible: true
+scrollbars is BarProp: true visible: true
+statusbar is BarProp: true visible: true
+toolbar is BarProp: true visible: true
diff --git a/Tests/LibWeb/Text/expected/all-window-properties.txt b/Tests/LibWeb/Text/expected/all-window-properties.txt
index df057954b11..4406c33fe37 100644
--- a/Tests/LibWeb/Text/expected/all-window-properties.txt
+++ b/Tests/LibWeb/Text/expected/all-window-properties.txt
@@ -23,6 +23,7 @@ AudioParam
 AudioScheduledSourceNode
 AudioTrack
 AudioTrackList
+BarProp
 BaseAudioContext
 BeforeUnloadEvent
 BigInt
diff --git a/Tests/LibWeb/Text/input/HTML/window-barprops.html b/Tests/LibWeb/Text/input/HTML/window-barprops.html
new file mode 100644
index 00000000000..c5fcbe24e02
--- /dev/null
+++ b/Tests/LibWeb/Text/input/HTML/window-barprops.html
@@ -0,0 +1,23 @@
+<!DOCTYPE html>
+<script src="../include.js"></script>
+<script>
+    test(() => {
+        const availableProps = [
+            "locationbar",
+            "menubar",
+            "personalbar",
+            "scrollbars",
+            "statusbar",
+            "toolbar",
+        ];
+
+        for (const propName of availableProps) {
+            const windowProp = window[propName];
+            println(
+                `${propName} is BarProp: ${windowProp instanceof BarProp} visible: ${
+                    windowProp.visible
+                }`
+            );
+        }
+    });
+</script>