diff --git a/Userland/Libraries/LibGUI/Application.cpp b/Userland/Libraries/LibGUI/Application.cpp
index fbd0c7260d..818fe37cd6 100644
--- a/Userland/Libraries/LibGUI/Application.cpp
+++ b/Userland/Libraries/LibGUI/Application.cpp
@@ -189,10 +189,10 @@ void Application::did_delete_last_window(Badge<Window>)
         m_event_loop->quit(0);
 }
 
-void Application::set_system_palette(SharedBuffer& buffer)
+void Application::set_system_palette(Core::AnonymousBuffer& buffer)
 {
     if (!m_system_palette)
-        m_system_palette = Gfx::PaletteImpl::create_with_shared_buffer(buffer);
+        m_system_palette = Gfx::PaletteImpl::create_with_anonymous_buffer(buffer);
     else
         m_system_palette->replace_internal_buffer({}, buffer);
 
diff --git a/Userland/Libraries/LibGUI/Application.h b/Userland/Libraries/LibGUI/Application.h
index 4114ef631d..32731c8853 100644
--- a/Userland/Libraries/LibGUI/Application.h
+++ b/Userland/Libraries/LibGUI/Application.h
@@ -71,7 +71,7 @@ public:
     Gfx::Palette palette() const;
     void set_palette(const Gfx::Palette&);
 
-    void set_system_palette(SharedBuffer&);
+    void set_system_palette(Core::AnonymousBuffer&);
 
     bool focus_debugging_enabled() const { return m_focus_debugging_enabled; }
     bool dnd_debugging_enabled() const { return m_dnd_debugging_enabled; }
diff --git a/Userland/Libraries/LibGUI/WindowServerConnection.cpp b/Userland/Libraries/LibGUI/WindowServerConnection.cpp
index 8540a924c8..b3167fff19 100644
--- a/Userland/Libraries/LibGUI/WindowServerConnection.cpp
+++ b/Userland/Libraries/LibGUI/WindowServerConnection.cpp
@@ -56,25 +56,23 @@ WindowServerConnection& WindowServerConnection::the()
     return *s_connection;
 }
 
-static void set_system_theme_from_shbuf_id(int id)
+static void set_system_theme_from_anonymous_buffer(Core::AnonymousBuffer buffer)
 {
-    auto system_theme = SharedBuffer::create_from_shbuf_id(id);
-    ASSERT(system_theme);
-    Gfx::set_system_theme(*system_theme);
-    Application::the()->set_system_palette(*system_theme);
+    Gfx::set_system_theme(buffer);
+    Application::the()->set_system_palette(buffer);
 }
 
 void WindowServerConnection::handshake()
 {
     auto response = send_sync<Messages::WindowServer::Greet>();
     set_my_client_id(response->client_id());
-    set_system_theme_from_shbuf_id(response->system_theme_buffer_id());
+    set_system_theme_from_anonymous_buffer(response->theme_buffer());
     Desktop::the().did_receive_screen_rect({}, response->screen_rect());
 }
 
 void WindowServerConnection::handle(const Messages::WindowClient::UpdateSystemTheme& message)
 {
-    set_system_theme_from_shbuf_id(message.system_theme_buffer_id());
+    set_system_theme_from_anonymous_buffer(message.theme_buffer());
     Window::update_all_windows({});
     Window::for_each_window({}, [](auto& window) {
         Core::EventLoop::current().post_event(window, make<ThemeChangeEvent>());
diff --git a/Userland/Libraries/LibGfx/Palette.cpp b/Userland/Libraries/LibGfx/Palette.cpp
index de6915d7ba..2616c4d06e 100644
--- a/Userland/Libraries/LibGfx/Palette.cpp
+++ b/Userland/Libraries/LibGfx/Palette.cpp
@@ -31,13 +31,13 @@
 
 namespace Gfx {
 
-NonnullRefPtr<PaletteImpl> PaletteImpl::create_with_shared_buffer(SharedBuffer& buffer)
+NonnullRefPtr<PaletteImpl> PaletteImpl::create_with_anonymous_buffer(Core::AnonymousBuffer buffer)
 {
-    return adopt(*new PaletteImpl(buffer));
+    return adopt(*new PaletteImpl(move(buffer)));
 }
 
-PaletteImpl::PaletteImpl(SharedBuffer& buffer)
-    : m_theme_buffer(buffer)
+PaletteImpl::PaletteImpl(Core::AnonymousBuffer buffer)
+    : m_theme_buffer(move(buffer))
 {
 }
 
@@ -52,7 +52,7 @@ Palette::~Palette()
 
 const SystemTheme& PaletteImpl::theme() const
 {
-    return *m_theme_buffer->data<SystemTheme>();
+    return *m_theme_buffer.data<SystemTheme>();
 }
 
 Color PaletteImpl::color(ColorRole role) const
@@ -75,9 +75,9 @@ String PaletteImpl::path(PathRole role) const
 
 NonnullRefPtr<PaletteImpl> PaletteImpl::clone() const
 {
-    auto new_theme_buffer = SharedBuffer::create_with_size(m_theme_buffer->size());
-    memcpy(new_theme_buffer->data<SystemTheme>(), &theme(), m_theme_buffer->size());
-    return adopt(*new PaletteImpl(*new_theme_buffer));
+    auto new_theme_buffer = Core::AnonymousBuffer::create_with_size(m_theme_buffer.size());
+    memcpy(new_theme_buffer.data<SystemTheme>(), &theme(), m_theme_buffer.size());
+    return adopt(*new PaletteImpl(move(new_theme_buffer)));
 }
 
 void Palette::set_color(ColorRole role, Color color)
@@ -109,9 +109,9 @@ PaletteImpl::~PaletteImpl()
 {
 }
 
-void PaletteImpl::replace_internal_buffer(Badge<GUI::Application>, SharedBuffer& buffer)
+void PaletteImpl::replace_internal_buffer(Badge<GUI::Application>, Core::AnonymousBuffer buffer)
 {
-    m_theme_buffer = buffer;
+    m_theme_buffer = move(buffer);
 }
 
 }
diff --git a/Userland/Libraries/LibGfx/Palette.h b/Userland/Libraries/LibGfx/Palette.h
index dfd47e90ff..65153ce1ba 100644
--- a/Userland/Libraries/LibGfx/Palette.h
+++ b/Userland/Libraries/LibGfx/Palette.h
@@ -41,7 +41,7 @@ class PaletteImpl : public RefCounted<PaletteImpl> {
 
 public:
     ~PaletteImpl();
-    static NonnullRefPtr<PaletteImpl> create_with_shared_buffer(SharedBuffer&);
+    static NonnullRefPtr<PaletteImpl> create_with_anonymous_buffer(Core::AnonymousBuffer);
     NonnullRefPtr<PaletteImpl> clone() const;
 
     Color color(ColorRole) const;
@@ -49,12 +49,12 @@ public:
     String path(PathRole) const;
     const SystemTheme& theme() const;
 
-    void replace_internal_buffer(Badge<GUI::Application>, SharedBuffer& buffer);
+    void replace_internal_buffer(Badge<GUI::Application>, Core::AnonymousBuffer buffer);
 
 private:
-    explicit PaletteImpl(SharedBuffer&);
+    explicit PaletteImpl(Core::AnonymousBuffer);
 
-    RefPtr<SharedBuffer> m_theme_buffer;
+    Core::AnonymousBuffer m_theme_buffer;
 };
 
 class Palette {
diff --git a/Userland/Libraries/LibGfx/SystemTheme.cpp b/Userland/Libraries/LibGfx/SystemTheme.cpp
index 5ccb04256d..7d48311dfa 100644
--- a/Userland/Libraries/LibGfx/SystemTheme.cpp
+++ b/Userland/Libraries/LibGfx/SystemTheme.cpp
@@ -33,7 +33,7 @@ namespace Gfx {
 
 static SystemTheme dummy_theme;
 static const SystemTheme* theme_page = &dummy_theme;
-static RefPtr<SharedBuffer> theme_buffer;
+static Core::AnonymousBuffer theme_buffer;
 
 const SystemTheme& current_system_theme()
 {
@@ -41,24 +41,24 @@ const SystemTheme& current_system_theme()
     return *theme_page;
 }
 
-int current_system_theme_buffer_id()
+Core::AnonymousBuffer& current_system_theme_buffer()
 {
-    ASSERT(theme_buffer);
-    return theme_buffer->shbuf_id();
+    ASSERT(theme_buffer.is_valid());
+    return theme_buffer;
 }
 
-void set_system_theme(SharedBuffer& buffer)
+void set_system_theme(Core::AnonymousBuffer buffer)
 {
-    theme_buffer = buffer;
-    theme_page = theme_buffer->data<SystemTheme>();
+    theme_buffer = move(buffer);
+    theme_page = theme_buffer.data<SystemTheme>();
 }
 
-RefPtr<SharedBuffer> load_system_theme(const String& path)
+Core::AnonymousBuffer load_system_theme(const String& path)
 {
     auto file = Core::ConfigFile::open(path);
-    auto buffer = SharedBuffer::create_with_size(sizeof(SystemTheme));
+    auto buffer = Core::AnonymousBuffer::create_with_size(sizeof(SystemTheme));
 
-    auto* data = buffer->data<SystemTheme>();
+    auto* data = buffer.data<SystemTheme>();
 
     auto get_color = [&](auto& name) {
         auto color_string = file->read_entry("Colors", name);
@@ -121,9 +121,6 @@ RefPtr<SharedBuffer> load_system_theme(const String& path)
 
     DO_PATH(TitleButtonIcons);
 
-    buffer->seal();
-    buffer->share_globally();
-
     return buffer;
 }
 
diff --git a/Userland/Libraries/LibGfx/SystemTheme.h b/Userland/Libraries/LibGfx/SystemTheme.h
index 60e382c65f..7c3fbbabb9 100644
--- a/Userland/Libraries/LibGfx/SystemTheme.h
+++ b/Userland/Libraries/LibGfx/SystemTheme.h
@@ -29,6 +29,7 @@
 #include <AK/Forward.h>
 #include <AK/String.h>
 #include <AK/Types.h>
+#include <LibCore/AnonymousBuffer.h>
 #include <LibGfx/Color.h>
 
 namespace Gfx {
@@ -153,9 +154,9 @@ struct SystemTheme {
 };
 
 const SystemTheme& current_system_theme();
-int current_system_theme_buffer_id();
-void set_system_theme(SharedBuffer&);
-RefPtr<SharedBuffer> load_system_theme(const String& path);
+Core::AnonymousBuffer& current_system_theme_buffer();
+void set_system_theme(Core::AnonymousBuffer);
+Core::AnonymousBuffer load_system_theme(const String& path);
 
 }
 
diff --git a/Userland/Libraries/LibWeb/OutOfProcessWebView.cpp b/Userland/Libraries/LibWeb/OutOfProcessWebView.cpp
index d30025d678..003571e2e8 100644
--- a/Userland/Libraries/LibWeb/OutOfProcessWebView.cpp
+++ b/Userland/Libraries/LibWeb/OutOfProcessWebView.cpp
@@ -43,7 +43,7 @@ OutOfProcessWebView::OutOfProcessWebView()
     set_should_hide_unnecessary_scrollbars(true);
     set_focus_policy(GUI::FocusPolicy::StrongFocus);
     m_client = WebContentClient::construct(*this);
-    client().post_message(Messages::WebContentServer::UpdateSystemTheme(Gfx::current_system_theme_buffer_id()));
+    client().post_message(Messages::WebContentServer::UpdateSystemTheme(Gfx::current_system_theme_buffer()));
 }
 
 OutOfProcessWebView::~OutOfProcessWebView()
@@ -140,7 +140,7 @@ void OutOfProcessWebView::mousemove_event(GUI::MouseEvent& event)
 void OutOfProcessWebView::theme_change_event(GUI::ThemeChangeEvent& event)
 {
     GUI::ScrollableWidget::theme_change_event(event);
-    client().post_message(Messages::WebContentServer::UpdateSystemTheme(Gfx::current_system_theme_buffer_id()));
+    client().post_message(Messages::WebContentServer::UpdateSystemTheme(Gfx::current_system_theme_buffer()));
     request_repaint();
 }
 
diff --git a/Userland/Services/WindowServer/ClientConnection.cpp b/Userland/Services/WindowServer/ClientConnection.cpp
index 3c8b10bfe7..482294de57 100644
--- a/Userland/Services/WindowServer/ClientConnection.cpp
+++ b/Userland/Services/WindowServer/ClientConnection.cpp
@@ -713,7 +713,7 @@ void ClientConnection::handle(const Messages::WindowServer::WM_SetWindowMinimize
 
 OwnPtr<Messages::WindowServer::GreetResponse> ClientConnection::handle(const Messages::WindowServer::Greet&)
 {
-    return make<Messages::WindowServer::GreetResponse>(client_id(), Screen::the().rect(), Gfx::current_system_theme_buffer_id());
+    return make<Messages::WindowServer::GreetResponse>(client_id(), Screen::the().rect(), Gfx::current_system_theme_buffer());
 }
 
 void ClientConnection::handle(const Messages::WindowServer::WM_SetWindowTaskbarRect& message)
@@ -836,7 +836,7 @@ void ClientConnection::handle(const Messages::WindowServer::SetWindowProgress& m
 void ClientConnection::handle(const Messages::WindowServer::RefreshSystemTheme&)
 {
     // Post the client an UpdateSystemTheme message to refresh its theme.
-    post_message(Messages::WindowClient::UpdateSystemTheme(Gfx::current_system_theme_buffer_id()));
+    post_message(Messages::WindowClient::UpdateSystemTheme(Gfx::current_system_theme_buffer()));
 }
 
 void ClientConnection::handle(const Messages::WindowServer::Pong&)
diff --git a/Userland/Services/WindowServer/WindowClient.ipc b/Userland/Services/WindowServer/WindowClient.ipc
index f3d04d5a9c..ad0952ca53 100644
--- a/Userland/Services/WindowServer/WindowClient.ipc
+++ b/Userland/Services/WindowServer/WindowClient.ipc
@@ -34,7 +34,7 @@ endpoint WindowClient = 4
 
     DragDropped(i32 window_id, Gfx::IntPoint mouse_position, [UTF8] String text, HashMap<String,ByteBuffer> mime_data) =|
 
-    UpdateSystemTheme(i32 system_theme_buffer_id) =|
+    UpdateSystemTheme(Core::AnonymousBuffer theme_buffer) =|
 
     DisplayLinkNotification() =|
 
diff --git a/Userland/Services/WindowServer/WindowManager.cpp b/Userland/Services/WindowServer/WindowManager.cpp
index ebc4529372..f0080ff427 100644
--- a/Userland/Services/WindowServer/WindowManager.cpp
+++ b/Userland/Services/WindowServer/WindowManager.cpp
@@ -1404,17 +1404,16 @@ Gfx::IntRect WindowManager::dnd_rect() const
 bool WindowManager::update_theme(String theme_path, String theme_name)
 {
     auto new_theme = Gfx::load_system_theme(theme_path);
-    if (!new_theme)
+    if (!new_theme.is_valid())
         return false;
-    ASSERT(new_theme);
-    Gfx::set_system_theme(*new_theme);
-    m_palette = Gfx::PaletteImpl::create_with_shared_buffer(*new_theme);
+    Gfx::set_system_theme(new_theme);
+    m_palette = Gfx::PaletteImpl::create_with_anonymous_buffer(new_theme);
     Compositor::the().set_background_color(palette().desktop_background().to_string());
     HashTable<ClientConnection*> notified_clients;
     for_each_window([&](Window& window) {
         if (window.client()) {
             if (!notified_clients.contains(window.client())) {
-                window.client()->post_message(Messages::WindowClient::UpdateSystemTheme(Gfx::current_system_theme_buffer_id()));
+                window.client()->post_message(Messages::WindowClient::UpdateSystemTheme(Gfx::current_system_theme_buffer()));
                 notified_clients.set(window.client());
             }
         }
diff --git a/Userland/Services/WindowServer/WindowServer.ipc b/Userland/Services/WindowServer/WindowServer.ipc
index 80ad93cdf8..3b528228f1 100644
--- a/Userland/Services/WindowServer/WindowServer.ipc
+++ b/Userland/Services/WindowServer/WindowServer.ipc
@@ -1,6 +1,6 @@
 endpoint WindowServer = 2
 {
-    Greet() => (i32 client_id, Gfx::IntRect screen_rect, i32 system_theme_buffer_id)
+    Greet() => (i32 client_id, Gfx::IntRect screen_rect, Core::AnonymousBuffer theme_buffer)
 
     CreateMenubar() => (i32 menubar_id)
     DestroyMenubar(i32 menubar_id) => ()
diff --git a/Userland/Services/WindowServer/main.cpp b/Userland/Services/WindowServer/main.cpp
index 8792c37467..1e6a0d8ce2 100644
--- a/Userland/Services/WindowServer/main.cpp
+++ b/Userland/Services/WindowServer/main.cpp
@@ -39,7 +39,7 @@
 
 int main(int, char**)
 {
-    if (pledge("stdio video thread sendfd recvfd shared_buffer accept rpath wpath cpath unix proc fattr sigaction", nullptr) < 0) {
+    if (pledge("stdio video thread sendfd recvfd accept rpath wpath cpath unix proc fattr sigaction", nullptr) < 0) {
         perror("pledge");
         return 1;
     }
@@ -78,13 +78,13 @@ int main(int, char**)
     auto theme_name = wm_config->read_entry("Theme", "Name", "Default");
 
     auto theme = Gfx::load_system_theme(String::formatted("/res/themes/{}.ini", theme_name));
-    ASSERT(theme);
-    Gfx::set_system_theme(*theme);
-    auto palette = Gfx::PaletteImpl::create_with_shared_buffer(*theme);
+    ASSERT(theme.is_valid());
+    Gfx::set_system_theme(theme);
+    auto palette = Gfx::PaletteImpl::create_with_anonymous_buffer(theme);
 
     WindowServer::EventLoop loop;
 
-    if (pledge("stdio video thread sendfd recvfd shared_buffer accept rpath wpath cpath proc", nullptr) < 0) {
+    if (pledge("stdio video thread sendfd recvfd accept rpath wpath cpath proc", nullptr) < 0) {
         perror("pledge");
         return 1;
     }