diff --git a/CMakeLists.txt b/CMakeLists.txt
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -45,7 +45,6 @@
 find_package(KF5ConfigWidgets ${KF5_DEP_VERSION} REQUIRED)
 find_package(KF5I18n ${KF5_DEP_VERSION} REQUIRED)
 find_package(KF5WidgetsAddons ${KF5_DEP_VERSION} REQUIRED)
-find_package(KF5WindowSystem ${KF5_DEP_VERSION} REQUIRED)
 find_package(KF5Sonnet ${KF5_DEP_VERSION} REQUIRED)
 
 set(EXCLUDE_DEPRECATED_BEFORE_AND_AT 0 CACHE STRING "Control the range of deprecated API excluded from the build [default=0].")
diff --git a/src/CMakeLists.txt b/src/CMakeLists.txt
--- a/src/CMakeLists.txt
+++ b/src/CMakeLists.txt
@@ -41,7 +41,6 @@
 PRIVATE
   KF5::SonnetCore
   KF5::ConfigWidgets
-  KF5::WindowSystem
   KF5::Completion
 )
 
diff --git a/src/findreplace/kfinddialog.h b/src/findreplace/kfinddialog.h
--- a/src/findreplace/kfinddialog.h
+++ b/src/findreplace/kfinddialog.h
@@ -53,7 +53,7 @@
  * To create a non-modal find dialog:
  * \code
  *   if (m_findDialog) {
- *     KWindowSystem::activateWindow(m_findDialog->winId());
+ *     m_findDialog->activateWindow();
  *   } else {
  *     m_findDialog = new KFindDialog(...);
  *     connect(m_findDialog, &KFindDialog::okClicked, this, [this] {
diff --git a/src/widgets/ktextedit.cpp b/src/widgets/ktextedit.cpp
--- a/src/widgets/ktextedit.cpp
+++ b/src/widgets/ktextedit.cpp
@@ -44,7 +44,6 @@
 #include <kstandardshortcut.h>
 #include <klocalizedstring.h>
 #include <kmessagebox.h>
-#include <kwindowsystem.h>
 
 #include "kreplacedialog.h"
 #include "kfinddialog.h"
@@ -799,7 +798,7 @@
     }
 
     if (d->repDlg) {
-        KWindowSystem::activateWindow(d->repDlg->winId());
+        d->repDlg->activateWindow();
     } else {
         d->repDlg = new KReplaceDialog(this, 0,
                                        QStringList(), QStringList(), false);
@@ -962,7 +961,7 @@
     }
 
     if (d->findDlg) {
-        KWindowSystem::activateWindow(d->findDlg->winId());
+        d->findDlg->activateWindow();
     } else {
         d->findDlg = new KFindDialog(this);
         connect(d->findDlg, &KFindDialog::okClicked, this, &KTextEdit::slotDoFind);
@@ -977,7 +976,7 @@
     }
 
     if (d->repDlg) {
-        KWindowSystem::activateWindow(d->repDlg->winId());
+        d->repDlg->activateWindow();
     } else {
         d->repDlg = new KReplaceDialog(this, 0,
                                        QStringList(), QStringList(), false);