diff --git a/examples/CMakeLists.txt b/examples/CMakeLists.txt
index c768457..cc3ce56 100644
--- a/examples/CMakeLists.txt
+++ b/examples/CMakeLists.txt
@@ -25,7 +25,7 @@
 if(FRAMELESSHELPER_BUILD_WIDGETS AND TARGET Qt${QT_VERSION_MAJOR}::Widgets)
     add_subdirectory(widget)
     add_subdirectory(mainwindow)
-    add_subdirectory(openglwidget)
+    #add_subdirectory(openglwidget) # Currently not functional.
     add_subdirectory(dialog)
 endif()
 
diff --git a/include/FramelessHelper/Core/framelesshelper_linux.h b/include/FramelessHelper/Core/framelesshelper_linux.h
index 68ed954..d1829d2 100644
--- a/include/FramelessHelper/Core/framelesshelper_linux.h
+++ b/include/FramelessHelper/Core/framelesshelper_linux.h
@@ -53,11 +53,14 @@
  * authorization from the authors.
  */
 
+// This one is not included in any public headers.
 using Display = struct _XDisplay;
 
 #if __has_include(<xcb/xcb.h>)
 #  include <xcb/xcb.h>
+#  define FRAMELESSHELPER_HAS_XCB
 #else // !__has_include(<xcb/xcb.h>)
+
 using xcb_connection_t = struct xcb_connection_t;
 using xcb_button_t = uint8_t;
 using xcb_window_t = uint32_t;
@@ -208,6 +211,7 @@ using xcb_list_properties_reply_t = struct xcb_list_properties_reply_t
 [[maybe_unused]] inline constexpr const char ATOM_NET_WM_DEEPIN_BLUR_REGION_ROUNDED[] = "_NET_WM_DEEPIN_BLUR_REGION_ROUNDED";
 [[maybe_unused]] inline constexpr const char ATOM_UTF8_STRING[] = "UTF8_STRING";
 
+#ifndef FRAMELESSHELPER_HAS_XCB
 extern "C"
 {
 
@@ -328,7 +332,7 @@ xcb_get_property_unchecked(
 );
 
 } // extern "C"
-
+#endif // FRAMELESSHELPER_HAS_XCB
 
 /* GTK - The GIMP Toolkit
  * Copyright (C) 1995-1997 Peter Mattis, Spencer Kimball and Josh MacDonald
@@ -355,8 +359,11 @@ xcb_get_property_unchecked(
  */
 
 #if __has_include(<gtk/gtk.h>)
+#  undef signals // Workaround a compilation issue caused by GTK.
 #  include <gtk/gtk.h>
+#  define FRAMELESSHELPER_HAS_GTK
 #else // !__has_include(<gtk/gtk.h>)
+
 #define G_VALUE_INIT  { 0, { { 0 } } }
 #define g_signal_connect(instance, detailed_signal, c_handler, data) \
     g_signal_connect_data((instance), (detailed_signal), (c_handler), (data), nullptr, G_CONNECT_DEFAULT)
@@ -378,7 +385,7 @@ using gint64 = signed long;
 using guint64 = unsigned long;
 using gsize = unsigned int;
 
-using GType = unsigned long;
+using GType = unsigned long; // TODO: or unsigned int?
 using GValue = struct _GValue;
 using GObject = struct _GObject;
 using GClosure = struct _GClosure;
@@ -417,7 +424,7 @@ struct _GValue
 [[maybe_unused]] inline constexpr const char GTK_THEME_NAME_PROP[] = "gtk-theme-name";
 [[maybe_unused]] inline constexpr const char GTK_THEME_PREFER_DARK_PROP[] = "gtk-application-prefer-dark-theme";
 
-#if 0
+#ifndef FRAMELESSHELPER_HAS_GTK
 extern "C"
 {
 
@@ -491,7 +498,15 @@ g_clear_object(
 );
 
 } // extern "C"
-#endif
+#endif // FRAMELESSHELPER_HAS_GTK
 
+FRAMELESSHELPER_BEGIN_NAMESPACE
 template<typename T>
-T gtkSettings(const gchar *property);
+[[nodiscard]] T gtkSettings(const gchar *property);
+
+#if (QT_VERSION >= QT_VERSION_CHECK(6, 0, 0))
+using x11_return_type = quint32;
+#else // (QT_VERSION < QT_VERSION_CHECK(6, 0, 0))
+using x11_return_type = unsigned long;
+#endif // (QT_VERSION >= QT_VERSION_CHECK(6, 0, 0))
+FRAMELESSHELPER_END_NAMESPACE
diff --git a/include/FramelessHelper/Core/utils.h b/include/FramelessHelper/Core/utils.h
index 77b222b..d79b723 100644
--- a/include/FramelessHelper/Core/utils.h
+++ b/include/FramelessHelper/Core/utils.h
@@ -144,15 +144,11 @@ FRAMELESSHELPER_CORE_API void bringWindowToFront(const WId windowId);
 #ifdef Q_OS_LINUX
 [[nodiscard]] FRAMELESSHELPER_CORE_API QScreen *x11_findScreenForVirtualDesktop
     (const int virtualDesktopNumber);
-#if (QT_VERSION < QT_VERSION_CHECK(6, 0, 0))
-[[nodiscard]] FRAMELESSHELPER_CORE_API unsigned long x11_appRootWindow(const int screen);
-#else // (QT_VERSION >= QT_VERSION_CHECK(6, 0, 0))
-[[nodiscard]] FRAMELESSHELPER_CORE_API quint32 x11_appRootWindow(const int screen);
-#endif // (QT_VERSION < QT_VERSION_CHECK(6, 0, 0))
+[[nodiscard]] FRAMELESSHELPER_CORE_API x11_return_type x11_appRootWindow(const int screen);
 [[nodiscard]] FRAMELESSHELPER_CORE_API int x11_appScreen();
-[[nodiscard]] FRAMELESSHELPER_CORE_API quint32 x11_appTime();
-[[nodiscard]] FRAMELESSHELPER_CORE_API quint32 x11_appUserTime();
-[[nodiscard]] FRAMELESSHELPER_CORE_API quint32 x11_getTimestamp();
+[[nodiscard]] FRAMELESSHELPER_CORE_API x11_return_type x11_appTime();
+[[nodiscard]] FRAMELESSHELPER_CORE_API x11_return_type x11_appUserTime();
+[[nodiscard]] FRAMELESSHELPER_CORE_API x11_return_type x11_getTimestamp();
 [[nodiscard]] FRAMELESSHELPER_CORE_API QByteArray x11_nextStartupId();
 [[nodiscard]] FRAMELESSHELPER_CORE_API Display *x11_display();
 [[nodiscard]] FRAMELESSHELPER_CORE_API xcb_connection_t *x11_connection();
diff --git a/src/core/CMakeLists.txt b/src/core/CMakeLists.txt
index 6144b19..cf9d281 100644
--- a/src/core/CMakeLists.txt
+++ b/src/core/CMakeLists.txt
@@ -24,10 +24,16 @@
 
 if(UNIX AND NOT APPLE)
     if(FRAMELESSHELPER_NO_PRIVATE)
-        find_package(Qt5 QUIET COMPONENTS X11Extras)
+        # Qt X11Extras is only available in Qt5.
+        if(QT_VERSION_MAJOR LESS 6)
+            find_package(Qt5 QUIET COMPONENTS X11Extras)
+        endif()
+    endif()
+    find_package(X11 QUIET)
+    find_package(PkgConfig QUIET)
+    if(PkgConfig_FOUND)
+        pkg_check_modules(GTK3 QUIET IMPORTED_TARGET gtk+-3.0)
     endif()
-    find_package(PkgConfig REQUIRED)
-    pkg_check_modules(GTK3 REQUIRED gtk+-3.0)
 endif()
 
 set(SUB_MOD_NAME Core)
@@ -137,7 +143,7 @@ add_library(${PROJECT_NAME}::${SUB_PROJ_NAME} ALIAS ${SUB_PROJ_NAME})
 add_library(${PROJECT_NAME}::${SUB_MOD_NAME} ALIAS ${SUB_PROJ_NAME})
 
 if(NOT FRAMELESSHELPER_NO_BUNDLE_RESOURCE)
-    if(${QT_VERSION} VERSION_GREATER_EQUAL 6.2)
+    if(QT_VERSION VERSION_GREATER_EQUAL "6.2")
         qt_add_resources(${SUB_PROJ_NAME} framelesshelpercore
             PREFIX
                 "/org.wangwenx190.${PROJECT_NAME}"
@@ -187,12 +193,22 @@ if(APPLE)
         "-framework AppKit"
     )
 elseif(UNIX)
-    target_include_directories(${SUB_PROJ_NAME} PRIVATE
-        ${GTK3_INCLUDE_DIRS}
-    )
-    target_link_libraries(${SUB_PROJ_NAME} PRIVATE
-        ${GTK3_LINK_LIBRARIES}
-    )
+    if(X11_FOUND)
+        target_link_libraries(${SUB_PROJ_NAME} PRIVATE
+            X11::xcb
+        )
+    endif()
+    if(GTK3_FOUND)
+        #target_include_directories(${SUB_PROJ_NAME} PRIVATE
+        #    ${GTK3_INCLUDE_DIRS}
+        #)
+        target_link_libraries(${SUB_PROJ_NAME} PRIVATE
+            PkgConfig::GTK3
+        )
+        target_compile_definitions(${SUB_PROJ_NAME} PRIVATE
+            GDK_VERSION_MIN_REQUIRED=GDK_VERSION_3_6
+        )
+    endif()
 endif()
 
 if(FRAMELESSHELPER_NO_PRIVATE)
diff --git a/src/core/platformsupport_linux.cpp b/src/core/platformsupport_linux.cpp
index b02562a..a149541 100644
--- a/src/core/platformsupport_linux.cpp
+++ b/src/core/platformsupport_linux.cpp
@@ -22,8 +22,13 @@
  * SOFTWARE.
  */
 
-#include "sysapiloader_p.h"
 #include "framelesshelper_linux.h"
+#include "sysapiloader_p.h"
+
+//////////////////////////////////////////////
+// XCB
+
+#ifndef FRAMELESSHELPER_HAS_XCB
 
 FRAMELESSHELPER_STRING_CONSTANT(libxcb)
 
@@ -44,9 +49,6 @@ FRAMELESSHELPER_STRING_CONSTANT(xcb_list_properties_atoms_length)
 FRAMELESSHELPER_STRING_CONSTANT(xcb_list_properties_atoms)
 FRAMELESSHELPER_STRING_CONSTANT(xcb_get_property_unchecked)
 
-//////////////////////////////////////////////
-// XCB
-
 extern "C" xcb_void_cookie_t
 xcb_send_event(
     xcb_connection_t *connection,
@@ -262,15 +264,19 @@ xcb_get_property_unchecked(
             _delete, window, property, type, long_offset, long_length);
 }
 
+#endif // FRAMELESSHELPER_HAS_XCB
+
 ///////////////////////////////////////////////////
 // GTK
 
-#if 0
-#define GTK_SETTINGS_IMPL(Name, Type, ...) \
-    Type Name(const gchar *property) \
+#ifndef FRAMELESSHELPER_HAS_GTK
+
+#define GTKSETTINGS_IMPL(Type, ...) \
+    Type gtkSettings(const gchar *property) \
     { \
         Q_ASSERT(property); \
-        if (!property) { \
+        Q_ASSERT(*property != '\0'); \
+        if (!property || (*property == '\0')) { \
             return Type{}; \
         } \
         static GtkSettings * const settings = gtk_settings_get_default(); \
@@ -441,10 +447,12 @@ g_clear_object(
     API_CALL_FUNCTION(g_clear_object, object_ptr);
 }
 
-GTK_SETTINGS_IMPL(GTK_bool, bool, const bool result = g_value_get_boolean(&value);)
-GTK_SETTINGS_IMPL(GTK_str, QString, const QString result = QUtf8String(g_value_get_string(&value));)
-#endif
+GTKSETTINGS_IMPL(bool, const bool result = g_value_get_boolean(&value);)
+GTKSETTINGS_IMPL(QString, const QString result = QUtf8String(g_value_get_string(&value));)
 
+#endif // FRAMELESSHELPER_HAS_GTK
+
+FRAMELESSHELPER_BEGIN_NAMESPACE
 template<typename T>
 T gtkSettings(const gchar *property)
 {
@@ -466,8 +474,14 @@ template bool gtkSettings<bool>(const gchar *);
 
 QString gtkSettings(const gchar *property)
 {
-    const auto raw = gtkSettings<gchar *>(property);
+    Q_ASSERT(property);
+    Q_ASSERT(*property != '\0');
+    if (!property || (*property == '\0')) {
+        return {};
+    }
+    const auto raw = gtkSettings<gchararray>(property);
     const QString result = QUtf8String(raw);
     g_free(raw);
     return result;
 }
+FRAMELESSHELPER_END_NAMESPACE
diff --git a/src/core/utils_linux.cpp b/src/core/utils_linux.cpp
index 8ccd3d7..b006785 100644
--- a/src/core/utils_linux.cpp
+++ b/src/core/utils_linux.cpp
@@ -44,11 +44,12 @@
 #  else // (QT_VERSION < QT_VERSION_CHECK(6, 0, 0))
 #    include <QtPlatformHeaders/qxcbscreenfunctions.h>
 #  endif // (QT_VERSION >= QT_VERSION_CHECK(6, 0, 0))
+#  if (QT_VERSION >= QT_VERSION_CHECK(6, 2, 0))
+#    include <QtGui/private/qtx11extras_p.h>
+#    define FRAMELESSHELPER_HAS_X11EXTRAS
+#  endif // (QT_VERSION >= QT_VERSION_CHECK(6, 2, 0))
 #endif // FRAMELESSHELPER_CORE_NO_PRIVATE
 
-extern template bool gtkSettings<bool>(const gchar *);
-extern QString gtkSettings(const gchar *);
-
 FRAMELESSHELPER_BEGIN_NAMESPACE
 
 Q_LOGGING_CATEGORY(lcUtilsLinux, "wangwenx190.framelesshelper.core.utils.linux")
@@ -81,6 +82,9 @@ FRAMELESSHELPER_BYTEARRAY_CONSTANT(connection)
 static constexpr const auto _XCB_SEND_EVENT_MASK =
     (XCB_EVENT_MASK_SUBSTRUCTURE_REDIRECT | XCB_EVENT_MASK_SUBSTRUCTURE_NOTIFY);
 
+extern template bool gtkSettings<bool>(const gchar *);
+extern QString gtkSettings(const gchar *);
+
 [[maybe_unused]] [[nodiscard]] static inline int
     qtEdgesToWmMoveOrResizeOperation(const Qt::Edges edges)
 {
@@ -143,20 +147,15 @@ QScreen *Utils::x11_findScreenForVirtualDesktop(const int virtualDesktopNumber)
 #endif // FRAMELESSHELPER_CORE_NO_PRIVATE
 }
 
-#if (QT_VERSION < QT_VERSION_CHECK(6, 0, 0))
-unsigned long Utils::x11_appRootWindow(const int screen)
-#else // (QT_VERSION >= QT_VERSION_CHECK(6, 0, 0))
-quint32 Utils::x11_appRootWindow(const int screen)
-#endif // (QT_VERSION < QT_VERSION_CHECK(6, 0, 0))
+x11_return_type Utils::x11_appRootWindow(const int screen)
 {
-#ifdef FRAMELESSHELPER_CORE_NO_PRIVATE
-#  ifdef FRAMELESSHELPER_HAS_X11EXTRAS
+#ifdef FRAMELESSHELPER_HAS_X11EXTRAS
     return QX11Info::appRootWindow(screen);
-#  else // !FRAMELESSHELPER_HAS_X11EXTRAS
+#else // !FRAMELESSHELPER_HAS_X11EXTRAS
+#  ifdef FRAMELESSHELPER_CORE_NO_PRIVATE
     Q_UNUSED(screen);
     return 0;
-#  endif // FRAMELESSHELPER_HAS_X11EXTRAS
-#else // !FRAMELESSHELPER_CORE_NO_PRIVATE
+#  else // !FRAMELESSHELPER_CORE_NO_PRIVATE
     if (!qApp) {
         return 0;
     }
@@ -169,18 +168,18 @@ quint32 Utils::x11_appRootWindow(const int screen)
         return 0;
     }
     return static_cast<xcb_window_t>(reinterpret_cast<quintptr>(native->nativeResourceForScreen(krootwindow, scr)));
-#endif // FRAMELESSHELPER_CORE_NO_PRIVATE
+#  endif // FRAMELESSHELPER_CORE_NO_PRIVATE
+#endif // FRAMELESSHELPER_HAS_X11EXTRAS
 }
 
 int Utils::x11_appScreen()
 {
-#ifdef FRAMELESSHELPER_CORE_NO_PRIVATE
-#  ifdef FRAMELESSHELPER_HAS_X11EXTRAS
+#ifdef FRAMELESSHELPER_HAS_X11EXTRAS
     return QX11Info::appScreen();
-#  else // !FRAMELESSHELPER_HAS_X11EXTRAS
+#else // !FRAMELESSHELPER_HAS_X11EXTRAS
+#  ifdef FRAMELESSHELPER_CORE_NO_PRIVATE
     return 0;
-#  endif // FRAMELESSHELPER_HAS_X11EXTRAS
-#else // !FRAMELESSHELPER_CORE_NO_PRIVATE
+#  else // !FRAMELESSHELPER_CORE_NO_PRIVATE
     if (!qApp) {
         return 0;
     }
@@ -189,18 +188,18 @@ int Utils::x11_appScreen()
         return 0;
     }
     return reinterpret_cast<qintptr>(native->nativeResourceForIntegration(kx11screen));
-#endif // FRAMELESSHELPER_CORE_NO_PRIVATE
+#  endif // FRAMELESSHELPER_CORE_NO_PRIVATE
+#endif // FRAMELESSHELPER_HAS_X11EXTRAS
 }
 
-quint32 Utils::x11_appTime()
+x11_return_type Utils::x11_appTime()
 {
-#ifdef FRAMELESSHELPER_CORE_NO_PRIVATE
-#  ifdef FRAMELESSHELPER_HAS_X11EXTRAS
+#ifdef FRAMELESSHELPER_HAS_X11EXTRAS
     return QX11Info::appTime();
-#  else // !FRAMELESSHELPER_HAS_X11EXTRAS
+#else // !FRAMELESSHELPER_HAS_X11EXTRAS
+#  ifdef FRAMELESSHELPER_CORE_NO_PRIVATE
     return 0;
-#  endif // FRAMELESSHELPER_HAS_X11EXTRAS
-#else // !FRAMELESSHELPER_CORE_NO_PRIVATE
+#  else // !FRAMELESSHELPER_CORE_NO_PRIVATE
     if (!qApp) {
         return 0;
     }
@@ -213,18 +212,18 @@ quint32 Utils::x11_appTime()
         return 0;
     }
     return static_cast<xcb_timestamp_t>(reinterpret_cast<quintptr>(native->nativeResourceForScreen(kapptime, screen)));
-#endif // FRAMELESSHELPER_CORE_NO_PRIVATE
+#  endif // FRAMELESSHELPER_CORE_NO_PRIVATE
+#endif // FRAMELESSHELPER_HAS_X11EXTRAS
 }
 
-quint32 Utils::x11_appUserTime()
+x11_return_type Utils::x11_appUserTime()
 {
-#ifdef FRAMELESSHELPER_CORE_NO_PRIVATE
-#  ifdef FRAMELESSHELPER_HAS_X11EXTRAS
+#ifdef FRAMELESSHELPER_HAS_X11EXTRAS
     return QX11Info::appUserTime();
-#  else // !FRAMELESSHELPER_HAS_X11EXTRAS
+#else // !FRAMELESSHELPER_HAS_X11EXTRAS
+#  ifdef FRAMELESSHELPER_CORE_NO_PRIVATE
     return 0;
-#  endif // FRAMELESSHELPER_HAS_X11EXTRAS
-#else // !FRAMELESSHELPER_CORE_NO_PRIVATE
+#  else // !FRAMELESSHELPER_CORE_NO_PRIVATE
     if (!qApp) {
         return 0;
     }
@@ -237,18 +236,18 @@ quint32 Utils::x11_appUserTime()
         return 0;
     }
     return static_cast<xcb_timestamp_t>(reinterpret_cast<quintptr>(native->nativeResourceForScreen(kappusertime, screen)));
-#endif // FRAMELESSHELPER_CORE_NO_PRIVATE
+#  endif // FRAMELESSHELPER_CORE_NO_PRIVATE
+#endif // FRAMELESSHELPER_HAS_X11EXTRAS
 }
 
-quint32 Utils::x11_getTimestamp()
+x11_return_type Utils::x11_getTimestamp()
 {
-#ifdef FRAMELESSHELPER_CORE_NO_PRIVATE
-#  ifdef FRAMELESSHELPER_HAS_X11EXTRAS
+#ifdef FRAMELESSHELPER_HAS_X11EXTRAS
     return QX11Info::getTimestamp();
-#  else // !FRAMELESSHELPER_HAS_X11EXTRAS
+#else // !FRAMELESSHELPER_HAS_X11EXTRAS
+#  ifdef FRAMELESSHELPER_CORE_NO_PRIVATE
     return 0;
-#  endif // FRAMELESSHELPER_HAS_X11EXTRAS
-#else // !FRAMELESSHELPER_CORE_NO_PRIVATE
+#  else // !FRAMELESSHELPER_CORE_NO_PRIVATE
     if (!qApp) {
         return 0;
     }
@@ -261,18 +260,18 @@ quint32 Utils::x11_getTimestamp()
         return 0;
     }
     return static_cast<xcb_timestamp_t>(reinterpret_cast<quintptr>(native->nativeResourceForScreen(kgettimestamp, screen)));
-#endif // FRAMELESSHELPER_CORE_NO_PRIVATE
+#  endif // FRAMELESSHELPER_CORE_NO_PRIVATE
+#endif // FRAMELESSHELPER_HAS_X11EXTRAS
 }
 
 QByteArray Utils::x11_nextStartupId()
 {
-#ifdef FRAMELESSHELPER_CORE_NO_PRIVATE
-#  ifdef FRAMELESSHELPER_HAS_X11EXTRAS
+#ifdef FRAMELESSHELPER_HAS_X11EXTRAS
     return QX11Info::nextStartupId();
-#  else // !FRAMELESSHELPER_HAS_X11EXTRAS
+#else // !FRAMELESSHELPER_HAS_X11EXTRAS
+#  ifdef FRAMELESSHELPER_CORE_NO_PRIVATE
     return {};
-#  endif // FRAMELESSHELPER_HAS_X11EXTRAS
-#else // !FRAMELESSHELPER_CORE_NO_PRIVATE
+#  else // !FRAMELESSHELPER_CORE_NO_PRIVATE
     if (!qApp) {
         return {};
     }
@@ -281,65 +280,66 @@ QByteArray Utils::x11_nextStartupId()
         return {};
     }
     return static_cast<char *>(native->nativeResourceForIntegration(kstartupid));
-#endif // FRAMELESSHELPER_CORE_NO_PRIVATE
+#  endif // FRAMELESSHELPER_CORE_NO_PRIVATE
+#endif // FRAMELESSHELPER_HAS_X11EXTRAS
 }
 
 Display *Utils::x11_display()
 {
-#ifdef FRAMELESSHELPER_CORE_NO_PRIVATE
-#  ifdef FRAMELESSHELPER_HAS_X11EXTRAS
+#ifdef FRAMELESSHELPER_HAS_X11EXTRAS
     return QX11Info::display();
-#  else // !FRAMELESSHELPER_HAS_X11EXTRAS
+#else // !FRAMELESSHELPER_HAS_X11EXTRAS
+#  ifdef FRAMELESSHELPER_CORE_NO_PRIVATE
     return nullptr;
-#  endif // FRAMELESSHELPER_HAS_X11EXTRAS
-#else // !FRAMELESSHELPER_CORE_NO_PRIVATE
+#  else // !FRAMELESSHELPER_CORE_NO_PRIVATE
     if (!qApp) {
         return nullptr;
     }
-#  if (QT_VERSION >= QT_VERSION_CHECK(6, 2, 0))
+#    if (QT_VERSION >= QT_VERSION_CHECK(6, 2, 0))
     using App = QNativeInterface::QX11Application;
     const auto native = qApp->nativeInterface<App>();
-#  else // (QT_VERSION < QT_VERSION_CHECK(6, 2, 0))
+#    else // (QT_VERSION < QT_VERSION_CHECK(6, 2, 0))
     const auto native = qApp->platformNativeInterface();
-#  endif // (QT_VERSION >= QT_VERSION_CHECK(6, 2, 0))
+#    endif // (QT_VERSION >= QT_VERSION_CHECK(6, 2, 0))
     if (!native) {
         return nullptr;
     }
-#  if (QT_VERSION >= QT_VERSION_CHECK(6, 2, 0))
+#    if (QT_VERSION >= QT_VERSION_CHECK(6, 2, 0))
     return native->display();
-#  else // (QT_VERSION < QT_VERSION_CHECK(6, 2, 0))
+#    else // (QT_VERSION < QT_VERSION_CHECK(6, 2, 0))
     return reinterpret_cast<Display *>(native->nativeResourceForIntegration(kdisplay));
-#  endif // (QT_VERSION >= QT_VERSION_CHECK(6, 2, 0))
-#endif // FRAMELESSHELPER_CORE_NO_PRIVATE
+#    endif // (QT_VERSION >= QT_VERSION_CHECK(6, 2, 0))
+#  endif // FRAMELESSHELPER_CORE_NO_PRIVATE
+#endif // FRAMELESSHELPER_HAS_X11EXTRAS
 }
 
 xcb_connection_t *Utils::x11_connection()
 {
-#ifdef FRAMELESSHELPER_CORE_NO_PRIVATE
-#  ifdef FRAMELESSHELPER_HAS_X11EXTRAS
+#ifdef FRAMELESSHELPER_HAS_X11EXTRAS
     return QX11Info::connection();
-#  else // !FRAMELESSHELPER_HAS_X11EXTRAS
+#else // !FRAMELESSHELPER_HAS_X11EXTRAS
+#  ifdef FRAMELESSHELPER_CORE_NO_PRIVATE
     return nullptr;
-#  endif // FRAMELESSHELPER_HAS_X11EXTRAS
-#else // !FRAMELESSHELPER_CORE_NO_PRIVATE
+#  else // !FRAMELESSHELPER_CORE_NO_PRIVATE
     if (!qApp) {
         return nullptr;
     }
-#  if (QT_VERSION >= QT_VERSION_CHECK(6, 2, 0))
+#    if (QT_VERSION >= QT_VERSION_CHECK(6, 2, 0))
     using App = QNativeInterface::QX11Application;
     const auto native = qApp->nativeInterface<App>();
-#  else // (QT_VERSION < QT_VERSION_CHECK(6, 2, 0))
+#    else // (QT_VERSION < QT_VERSION_CHECK(6, 2, 0))
     const auto native = qApp->platformNativeInterface();
-#  endif // (QT_VERSION >= QT_VERSION_CHECK(6, 2, 0))
+#    endif // (QT_VERSION >= QT_VERSION_CHECK(6, 2, 0))
     if (!native) {
         return nullptr;
     }
-#  if (QT_VERSION >= QT_VERSION_CHECK(6, 2, 0))
+#    if (QT_VERSION >= QT_VERSION_CHECK(6, 2, 0))
     return native->connection();
-#  else // (QT_VERSION < QT_VERSION_CHECK(6, 2, 0))
+#    else // (QT_VERSION < QT_VERSION_CHECK(6, 2, 0))
     return reinterpret_cast<xcb_connection_t *>(native->nativeResourceForIntegration(kconnection));
-#  endif // (QT_VERSION >= QT_VERSION_CHECK(6, 2, 0))
-#endif // FRAMELESSHELPER_CORE_NO_PRIVATE
+#    endif // (QT_VERSION >= QT_VERSION_CHECK(6, 2, 0))
+#  endif // FRAMELESSHELPER_CORE_NO_PRIVATE
+#endif // FRAMELESSHELPER_HAS_X11EXTRAS
 }
 
 SystemTheme Utils::getSystemTheme()