diff --git a/kcms/fonts/fontsaasettings.h b/kcms/fonts/fontsaasettings.h
--- a/kcms/fonts/fontsaasettings.h
+++ b/kcms/fonts/fontsaasettings.h
@@ -35,6 +35,7 @@
     Q_PROPERTY(int dpi READ dpi WRITE setDpi NOTIFY dpiChanged)
     Q_PROPERTY(KXftConfig::SubPixel::Type subPixel READ subPixel WRITE setSubPixel NOTIFY subPixelChanged)
     Q_PROPERTY(KXftConfig::Hint::Style hinting READ hinting WRITE setHinting NOTIFY hintingChanged)
+    Q_PROPERTY(bool isImmutable READ isImmutable CONSTANT)
 
 public:
     FontsAASettings(QObject *parent = nullptr);
@@ -46,6 +47,7 @@
     int dpi() const;
     KXftConfig::SubPixel::Type subPixel() const;
     KXftConfig::Hint::Style hinting() const;
+    bool isImmutable() const;
 
     void setExclude(bool exclude);
     void setExcludeFrom(int excludeFrom);
@@ -67,6 +69,7 @@
 
 private:
     FontAASettingsStore *m_fontAASettingsStore;
+    bool m_isImmutable = false;
     bool usrSave() override;
 
     using NotifySignalType = void (FontsAASettings::*)();
diff --git a/kcms/fonts/fontsaasettings.cpp b/kcms/fonts/fontsaasettings.cpp
--- a/kcms/fonts/fontsaasettings.cpp
+++ b/kcms/fonts/fontsaasettings.cpp
@@ -103,6 +103,11 @@
         m_excludeTo = excludeTo;
     }
 
+    bool isImmutable() const
+    {
+        return m_isImmutable;
+    }
+
     bool antiAliasing() const
     {
         return m_antiAliasing;
@@ -228,6 +233,7 @@
 
         KSharedConfig::Ptr config = KSharedConfig::openConfig("kdeglobals");
         KConfigGroup cg(config, "General");
+        m_isImmutable = cg.isEntryImmutable("XftAntialias");
         const auto aaState = xft.getAntiAliasing();
         setAntiAliasing(aaState != KXftConfig::AntiAliasing::Disabled);
 
@@ -238,6 +244,7 @@
 
 private:
     FontsAASettings *m_settings;
+    bool m_isImmutable;
     bool m_antiAliasing;
     bool m_antiAliasingChanged;
     KXftConfig::SubPixel::Type m_subPixel;
@@ -354,6 +361,11 @@
     findItem("hinting")->setProperty(hinting);
 }
 
+bool FontsAASettings::isImmutable() const
+{
+    return m_fontAASettingsStore->isImmutable();
+}
+
 bool FontsAASettings::usrSave()
 {
     m_fontAASettingsStore->save();
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
@@ -112,21 +112,22 @@
                 Kirigami.FormData.label: i18n("Anti-Aliasing:")
                 text: i18n("Enable")
                 Layout.fillWidth: true
+                enabled: !kcm.fontsAASettings.isImmutable
             }
 
             QtControls.CheckBox {
                 id: excludeCheckBox
                 checked: kcm.fontsAASettings.exclude
                 onCheckedChanged: kcm.fontsAASettings.exclude = checked;
                 text: i18n("Exclude range from anti-aliasing")
                 Layout.fillWidth: true
-                enabled: antiAliasingCheckBox.checked
+                enabled: antiAliasingCheckBox.checked && !kcm.fontsAASettings.isImmutable
             }
 
             RowLayout {
                 id: excludeField
                 Layout.preferredWidth: formLayout.maxImplicitWidth
-                enabled: antiAliasingCheckBox.checked
+                enabled: antiAliasingCheckBox.checked && !kcm.fontsAASettings.isImmutable
                 QtControls.SpinBox {
                     id: excludeFromSpinBox
                     stepSize: 1
@@ -142,7 +143,7 @@
                     Layout.fillWidth: true
                     horizontalAlignment: Text.AlignHCenter
                     text: i18n("to")
-                    enabled: excludeCheckBox.checked
+                    enabled: excludeCheckBox.checked && !kcm.fontsAASettings.isImmutable
                 }
 
                 QtControls.SpinBox {
@@ -152,7 +153,7 @@
                     textFromValue: function(value, locale) { return i18n("%1 pt", value)}
                     valueFromText: function(text, locale) { return parseInt(text) }
                     editable: true
-                    enabled: excludeCheckBox.checked
+                    enabled: excludeCheckBox.checked && !kcm.fontsAASettings.isImmutable
                     value: kcm.fontsAASettings.excludeTo
                 }
                 Connections {
@@ -170,7 +171,7 @@
                 onCurrentIndexChanged: kcm.subPixelCurrentIndex = currentIndex;
                 model: kcm.subPixelOptionsModel
                 textRole: "display"
-                enabled: antiAliasingCheckBox.checked
+                enabled: antiAliasingCheckBox.checked && !kcm.fontsAASettings.isImmutable
                 popup.height: popup.implicitHeight
                 delegate: QtControls.ItemDelegate {
                     id: subPixelDelegate
@@ -207,7 +208,7 @@
                 onCurrentTextChanged: kcm.hintingCurrentIndex = currentIndex;
                 model: kcm.hintingOptionsModel
                 textRole: "display"
-                enabled: antiAliasingCheckBox.checked
+                enabled: antiAliasingCheckBox.checked && !kcm.fontsAASettings.isImmutable
                 popup.height: popup.implicitHeight
                 delegate: QtControls.ItemDelegate {
                     id: hintingDelegate
@@ -239,6 +240,7 @@
             RowLayout {
                 QtControls.CheckBox {
                     id: dpiCheckBox
+                    enabled: !kcm.fontsAASettings.isImmutable
                     checked: kcm.fontsAASettings.dpi !== 0
                     text: i18n("Force font DPI:")
                     onClicked: kcm.fontsAASettings.dpi = (checked ? dpiSpinBox.value : 0)
@@ -248,7 +250,7 @@
                     id: dpiSpinBox
                     stepSize: 24
                     editable: true
-                    enabled: dpiCheckBox.checked
+                    enabled: dpiCheckBox.checked && !kcm.fontsAASettings.isImmutable
                     value: kcm.fontsAASettings.dpi !== 0 ? kcm.fontsAASettings.dpi : 96
                     onValueModified: kcm.fontsAASettings.dpi = value
                     // to: need to divide to stepSize