diff --git a/decorations/decorationbridge.h b/decorations/decorationbridge.h
index 6f51a3f..80c30f8 100644
--- a/decorations/decorationbridge.h
+++ b/decorations/decorationbridge.h
@@ -61,7 +61,7 @@ public:
 
     std::unique_ptr<KDecoration2::DecoratedClientPrivate> createClient(KDecoration2::DecoratedClient *client, KDecoration2::Decoration *decoration) override;
     std::unique_ptr<KDecoration2::DecorationSettingsPrivate> settings(KDecoration2::DecorationSettings *parent) override;
-    void update(KDecoration2::Decoration *decoration, const QRect &geometry) override;
+    void update(KDecoration2::Decoration *decoration, const QRect &geometry);
 
     bool needsBlur() const {
         return m_blur;
diff --git a/effects.cpp b/effects.cpp
index 9f765aa..bd2fad6 100644
--- a/effects.cpp
+++ b/effects.cpp
@@ -86,7 +86,7 @@ static QByteArray readWindowProperty(xcb_window_t win, xcb_atom_t atom, xcb_atom
     }
 }
 
-static void deleteWindowProperty(Window win, long int atom)
+static void deleteWindowProperty(xcb_window_t win, long int atom)
 {
     if (win == XCB_WINDOW_NONE) {
         return;
diff --git a/kcmkwin/kwindecoration/declarative-plugin/previewbridge.h b/kcmkwin/kwindecoration/declarative-plugin/previewbridge.h
index 7e1d8f3..7666dfb 100644
--- a/kcmkwin/kwindecoration/declarative-plugin/previewbridge.h
+++ b/kcmkwin/kwindecoration/declarative-plugin/previewbridge.h
@@ -47,7 +47,7 @@ public:
     explicit PreviewBridge(QObject *parent = nullptr);
     ~PreviewBridge() override;
     std::unique_ptr<DecoratedClientPrivate> createClient(DecoratedClient *client, Decoration *decoration) override;
-    void update(Decoration* decoration, const QRect& geometry) override;
+    void update(Decoration* decoration, const QRect& geometry);
     std::unique_ptr<DecorationSettingsPrivate> settings(DecorationSettings *parent) override;
 
     PreviewClient *lastCreatedClient() {
diff --git a/plugins/platforms/x11/common/eglonxbackend.h b/plugins/platforms/x11/common/eglonxbackend.h
index bd9c69b..72ebb68 100644
--- a/plugins/platforms/x11/common/eglonxbackend.h
+++ b/plugins/platforms/x11/common/eglonxbackend.h
@@ -30,6 +30,9 @@ along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
 #include <xcb/xcb.h>
 
+#include <X11/Xlib-xcb.h>
+#include <fixx11h.h>
+
 namespace KWin
 {
 
diff --git a/plugins/platforms/x11/standalone/x11_platform.h b/plugins/platforms/x11/standalone/x11_platform.h
index 5b75af3..9456341 100644
--- a/plugins/platforms/x11/standalone/x11_platform.h
+++ b/plugins/platforms/x11/standalone/x11_platform.h
@@ -33,6 +33,9 @@ along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
 #include <memory>
 
+#include <X11/Xlib-xcb.h>
+#include <fixx11h.h>
+
 namespace KWin
 {
 class SyncFilter;
diff --git a/plugins/platforms/x11/windowed/x11windowed_backend.cpp b/plugins/platforms/x11/windowed/x11windowed_backend.cpp
index be48ca2..caf026c 100644
--- a/plugins/platforms/x11/windowed/x11windowed_backend.cpp
+++ b/plugins/platforms/x11/windowed/x11windowed_backend.cpp
@@ -45,6 +45,7 @@ along with this program.  If not, see <http://www.gnu.org/licenses/>.
 // system
 #include <linux/input.h>
 #include <X11/Xlib-xcb.h>
+#include <X11/keysym.h>
 
 namespace KWin
 {
diff --git a/workspace.cpp b/workspace.cpp
index 2c682af..7172771 100644
--- a/workspace.cpp
+++ b/workspace.cpp
@@ -455,7 +455,7 @@ void Workspace::initWithX11()
     }
 
     // TODO: better value
-    rootInfo->setActiveWindow(None);
+    rootInfo->setActiveWindow(XCB_WINDOW_NONE);
     focusToNull();
 
     if (!qApp->isSessionRestored())