diff --git a/CMakeLists.txt b/CMakeLists.txt
index 03f33f57b4..369ffa5998 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -51,6 +51,11 @@ include(ECMConfiguredInstall)
 
 add_definitions(-DQT_DISABLE_DEPRECATED_BEFORE=0 -DQT_USE_QSTRINGBUILDER -DQT_NO_URL_CAST_FROM_STRING)
 
+# Prevent EGL headers from including platform headers, in particular Xlib.h.
+add_definitions(-DMESA_EGL_NO_X11_HEADERS)
+add_definitions(-DEGL_NO_X11)
+add_definitions(-DEGL_NO_PLATFORM_SPECIFIC_TYPES)
+
 set(CMAKE_CXX_STANDARD 17)
 set(CMAKE_CXX_STANDARD_REQUIRED ON)
 
diff --git a/platform.h b/platform.h
index ba41343a1a..03fbf838db 100644
--- a/platform.h
+++ b/platform.h
@@ -11,7 +11,6 @@
 #include <kwin_export.h>
 #include <kwinglobals.h>
 #include <epoxy/egl.h>
-#include <fixx11h.h>
 #include "fixqopengl.h"
 #include "input.h"
 
diff --git a/platformsupport/scenes/opengl/abstract_egl_backend.h b/platformsupport/scenes/opengl/abstract_egl_backend.h
index b72c362317..6f0babb9a2 100644
--- a/platformsupport/scenes/opengl/abstract_egl_backend.h
+++ b/platformsupport/scenes/opengl/abstract_egl_backend.h
@@ -13,7 +13,6 @@
 
 #include <QObject>
 #include <epoxy/egl.h>
-#include <fixx11h.h>
 
 class QOpenGLFramebufferObject;
 
diff --git a/plugins/platforms/drm/drm_gpu.h b/plugins/platforms/drm/drm_gpu.h
index 078c87e8d8..ca8c0c6f6d 100644
--- a/plugins/platforms/drm/drm_gpu.h
+++ b/plugins/platforms/drm/drm_gpu.h
@@ -14,7 +14,6 @@
 #include <QVector>
 
 #include <epoxy/egl.h>
-#include <fixx11h.h>
 
 #include "drm_buffer.h"
 
diff --git a/plugins/qpa/backingstore.h b/plugins/qpa/backingstore.h
index 51741a8800..d8df8db5cc 100644
--- a/plugins/qpa/backingstore.h
+++ b/plugins/qpa/backingstore.h
@@ -12,7 +12,6 @@
 
 #include <epoxy/egl.h>
 #include "fixqopengl.h"
-#include <fixx11h.h>
 
 #include <qpa/qplatformbackingstore.h>
 
diff --git a/plugins/qpa/eglhelpers.h b/plugins/qpa/eglhelpers.h
index 80f633b9d3..1db82c349d 100644
--- a/plugins/qpa/eglhelpers.h
+++ b/plugins/qpa/eglhelpers.h
@@ -11,7 +11,6 @@
 
 #include <epoxy/egl.h>
 #include "fixqopengl.h"
-#include <fixx11h.h>
 
 #include <QSurfaceFormat>
 
diff --git a/plugins/qpa/eglplatformcontext.h b/plugins/qpa/eglplatformcontext.h
index 07ae3e3a36..9d5986def3 100644
--- a/plugins/qpa/eglplatformcontext.h
+++ b/plugins/qpa/eglplatformcontext.h
@@ -12,7 +12,7 @@
 
 #include <epoxy/egl.h>
 #include "fixqopengl.h"
-#include <fixx11h.h>
+
 #include <qpa/qplatformopenglcontext.h>
 
 namespace KWin
diff --git a/plugins/qpa/integration.h b/plugins/qpa/integration.h
index 5d31ab6e10..daba012844 100644
--- a/plugins/qpa/integration.h
+++ b/plugins/qpa/integration.h
@@ -13,7 +13,6 @@
 #include <epoxy/egl.h>
 #include "fixqopengl.h"
 
-#include <fixx11h.h>
 #include <qpa/qplatformintegration.h>
 #include <QObject>
 
diff --git a/plugins/qpa/offscreensurface.h b/plugins/qpa/offscreensurface.h
index 9a17e0e2e5..0bf192e21b 100644
--- a/plugins/qpa/offscreensurface.h
+++ b/plugins/qpa/offscreensurface.h
@@ -11,7 +11,6 @@
 
 #include <epoxy/egl.h>
 #include "fixqopengl.h"
-#include <fixx11h.h>
 
 #include <qpa/qplatformoffscreensurface.h>
 
diff --git a/plugins/qpa/window.h b/plugins/qpa/window.h
index c1a7e75a35..f1270e1821 100644
--- a/plugins/qpa/window.h
+++ b/plugins/qpa/window.h
@@ -12,7 +12,6 @@
 
 #include <epoxy/egl.h>
 #include "fixqopengl.h"
-#include <fixx11h.h>
 
 #include <QPointer>
 #include <qpa/qplatformwindow.h>
diff --git a/plugins/screencast/eglnativefence.h b/plugins/screencast/eglnativefence.h
index c8dfd278a0..15886eae39 100644
--- a/plugins/screencast/eglnativefence.h
+++ b/plugins/screencast/eglnativefence.h
@@ -6,8 +6,9 @@
 
 #pragma once
 
+#include <QtGlobal>
+
 #include <epoxy/egl.h>
-#include <fixx11h.h>
 
 namespace KWin
 {