diff --git a/CMakeLists.txt b/CMakeLists.txt
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -54,6 +54,7 @@
     Activities
     ActivitiesStats
     Config
+    WidgetsAddons
 )
 
 find_package(KF5Kirigami2 ${KF5_MIN_VERSION} CONFIG)
diff --git a/kcms/fonts/CMakeLists.txt b/kcms/fonts/CMakeLists.txt
--- a/kcms/fonts/CMakeLists.txt
+++ b/kcms/fonts/CMakeLists.txt
@@ -30,6 +30,7 @@
         KF5::PlasmaQuick
         KF5::Declarative
         KF5::QuickAddons
+        KF5::WidgetsAddons
         PW::KWorkspace)
     if(FONTCONFIG_FOUND)
         target_link_libraries(kcm_fonts ${FONTCONFIG_LIBRARIES})
diff --git a/kcms/fonts/fonts.h b/kcms/fonts/fonts.h
--- a/kcms/fonts/fonts.h
+++ b/kcms/fonts/fonts.h
@@ -67,6 +67,7 @@
     void load() override;
     void save() override;
     Q_INVOKABLE void adjustAllFonts();
+    Q_INVOKABLE void adjustFont(const QFont &font, const QString &category);
 
 Q_SIGNALS:
     void fontsHaveChanged();
diff --git a/kcms/fonts/fonts.cpp b/kcms/fonts/fonts.cpp
--- a/kcms/fonts/fonts.cpp
+++ b/kcms/fonts/fonts.cpp
@@ -31,7 +31,6 @@
 #include <QWindow>
 #include <QQmlEngine>
 #include <QQuickView>
-#include <QFontDialog>
 #include <QApplication>
 #include <QFontDatabase>
 
@@ -42,7 +41,7 @@
 #include <KAboutData>
 #include <KLocalizedString>
 #include <KPluginFactory>
-#include <KFontDialog>
+#include <KFontChooserDialog>
 #include <KWindowSystem>
 
 #include "../krdb/krdb.h"
@@ -230,30 +229,43 @@
     emit fontsHaveChanged();
 }
 
+void KFonts::adjustFont(const QFont &font, const QString &category)
+{
+    QFont selFont = font;
+    int ret = KFontChooserDialog::getFont(selFont, KFontChooser::NoDisplayFlags);
+
+    if (ret == QDialog::Accepted) {
+        if (category == QLatin1String("font")) {
+            m_settings->setFont(selFont);
+        } else if (category == QLatin1String("menuFont")) {
+            m_settings->setMenuFont(selFont);
+        } else if (category == QLatin1String("toolBarFont")) {
+            m_settings->setToolBarFont(selFont);
+        } else if (category == QLatin1String("activeFont")) {
+            m_settings->setActiveFont(selFont);
+        } else if (category == QLatin1String("smallestReadableFont")) {
+            m_settings->setSmallestReadableFont(selFont);
+        } else if (category == QLatin1String("fixed")) {
+            m_settings->setFixed(selFont);
+        }
+    }
+}
+
 void KFonts::adjustAllFonts()
 {
     QFont font = m_settings->font();
     KFontChooser::FontDiffFlags fontDiffFlags;
-    int ret = KFontDialog::getFontDiff(font, fontDiffFlags, KFontChooser::NoDisplayFlags);
+    int ret = KFontChooserDialog::getFontDiff(font, fontDiffFlags, KFontChooser::NoDisplayFlags);
+
+    if (ret == QDialog::Accepted && fontDiffFlags) {
+        m_settings->setFont(applyFontDiff(m_settings->font(), font, fontDiffFlags));
+        m_settings->setMenuFont(applyFontDiff(m_settings->menuFont(), font, fontDiffFlags));
+        m_settings->setToolBarFont(applyFontDiff(m_settings->toolBarFont(), font, fontDiffFlags));
+        m_settings->setActiveFont(applyFontDiff(m_settings->activeFont(), font, fontDiffFlags));
+        m_settings->setSmallestReadableFont(applyFontDiff(m_settings->smallestReadableFont(), font, fontDiffFlags));
 
-    if (ret == KDialog::Accepted && fontDiffFlags) {
-        if (!m_settings->isImmutable("font")) {
-            m_settings->setFont(applyFontDiff(m_settings->font(), font, fontDiffFlags));
-        }
-        if (!m_settings->isImmutable("menuFont")) {
-            m_settings->setMenuFont(applyFontDiff(m_settings->menuFont(), font, fontDiffFlags));
-        }
-        if (!m_settings->isImmutable("toolBarFont")) {
-            m_settings->setToolBarFont(applyFontDiff(m_settings->toolBarFont(), font, fontDiffFlags));
-        }
-        if (!m_settings->isImmutable("activeFont")) {
-            m_settings->setActiveFont(applyFontDiff(m_settings->activeFont(), font, fontDiffFlags));
-        }
-        if (!m_settings->isImmutable("smallestReadableFont")) {
-            m_settings->setSmallestReadableFont(applyFontDiff(m_settings->smallestReadableFont(), font, fontDiffFlags));
-        }
         const QFont adjustedFont = applyFontDiff(m_settings->fixed(), font, fontDiffFlags);
-        if (QFontInfo(adjustedFont).fixedPitch() && !m_settings->isImmutable("fixed")) {
+        if (QFontInfo(adjustedFont).fixedPitch()) {
             m_settings->setFixed(adjustedFont);
         }
     }
diff --git a/kcms/fonts/package/contents/ui/FontWidget.qml b/kcms/fonts/package/contents/ui/FontWidget.qml
--- a/kcms/fonts/package/contents/ui/FontWidget.qml
+++ b/kcms/fonts/package/contents/ui/FontWidget.qml
@@ -57,11 +57,8 @@
             Kirigami.MnemonicData.enabled: false
             focus: true
             onClicked: {
-                fontDialog.adjustAllFonts = false;
-                fontDialog.currentCategory = root.category
-                fontDialog.font = root.font;
-                fontDialog.currentFont = root.font;
-                fontDialog.open()
+                fontDialog.adjustAllFonts = false
+                kcm.adjustFont(root.font, root.category)
             }
             QtControls.ToolTip {
                 visible: parent.hovered
diff --git a/kcms/fonts/package/contents/ui/main.qml b/kcms/fonts/package/contents/ui/main.qml
--- a/kcms/fonts/package/contents/ui/main.qml
+++ b/kcms/fonts/package/contents/ui/main.qml
@@ -266,9 +266,9 @@
                 property bool adjustAllFonts: false
                 onAccepted: {
                     if (adjustAllFonts) {
-                        kcm.adjustAllFonts(font);
+                        kcm.adjustAllFonts()
                     } else {
-                        kcm.fontsSettings[currentCategory] = font;
+                        kcm.adjustFont(font, currentCategory)
                     }
                 }
             }