diff --git a/CMakeLists.txt b/CMakeLists.txt
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -34,7 +34,6 @@
 find_package(KF5Config ${KF5_MIN_VERSION} CONFIG REQUIRED)
 find_package(KF5WidgetsAddons ${KF5_MIN_VERSION} CONFIG REQUIRED)
 find_package(KF5Completion ${KF5_MIN_VERSION} CONFIG REQUIRED)
-find_package(KF5WindowSystem ${KF5_MIN_VERSION} CONFIG REQUIRED)
 find_package(KF5CoreAddons ${KF5_MIN_VERSION} CONFIG REQUIRED)
 find_package(KF5Codecs ${KF5_MIN_VERSION} CONFIG REQUIRED)
 find_package(KF5ItemModels ${KF5_MIN_VERSION} CONFIG REQUIRED)
diff --git a/src/CMakeLists.txt b/src/CMakeLists.txt
--- a/src/CMakeLists.txt
+++ b/src/CMakeLists.txt
@@ -74,7 +74,6 @@
                                                 KF5::Completion
                                                 KF5::ConfigCore
                                                 KF5::CoreAddons
-                                                KF5::WindowSystem
                                                 KF5::WidgetsAddons
                                                 KF5::ItemModels
                                                 KF5::Codecs)
diff --git a/src/ui/keyselectiondialog.cpp b/src/ui/keyselectiondialog.cpp
--- a/src/ui/keyselectiondialog.cpp
+++ b/src/ui/keyselectiondialog.cpp
@@ -51,7 +51,6 @@
 
 // KDE
 #include <KLocalizedString>
-#include <kwindowsystem.h>
 #include <kconfig.h>
 #include <kmessagebox.h>
 #include <QPushButton>
@@ -513,9 +512,6 @@
 
     if (qApp) {
         QSize dialogSize(sizeHint());
-        KWindowSystem::setIcons(winId(), qApp->windowIcon().pixmap(32, 32),
-                                qApp->windowIcon().pixmap(16, 16));
-
         KConfigGroup dialogConfig(KSharedConfig::openConfig(), "Key Selection Dialog");
         dialogSize = dialogConfig.readEntry("Dialog size", dialogSize);
         const QByteArray headerState = dialogConfig.readEntry("header", QByteArray());