diff --git a/modules/misc/qt/kconfig.nix b/modules/misc/qt/kconfig.nix
index 58b776749..4d055734b 100644
--- a/modules/misc/qt/kconfig.nix
+++ b/modules/misc/qt/kconfig.nix
@@ -65,9 +65,9 @@ in
             if v == null then
               "--delete"
             else if t == "bool" then
-              "--type bool ${builtins.toJSON v}"
+              "--type bool -- ${builtins.toJSON v}"
             else
-              lib.escapeShellArg (toString v);
+              "-- ${lib.escapeShellArg (toString v)}";
           toLine =
             file: path: value:
             if builtins.isAttrs value then
diff --git a/tests/modules/misc/qt/qt-basic.nix b/tests/modules/misc/qt/qt-basic.nix
index d0e8a2c3e..44fdb2f1f 100644
--- a/tests/modules/misc/qt/qt-basic.nix
+++ b/tests/modules/misc/qt/qt-basic.nix
@@ -1,10 +1,14 @@
 {
   qt.enable = true;
 
+  qt.kde.settings.powerdevilrc.AC.Display.DimDisplayIdleTimeoutSec = -1;
+
   nmt.script = ''
     assertFileRegex home-path/etc/profile.d/hm-session-vars.sh \
       'QT_PLUGIN_PATH'
     assertFileRegex home-path/etc/profile.d/hm-session-vars.sh \
       'QML2_IMPORT_PATH'
+    assertFileRegex activate \
+      "kwriteconfig6 .*--file '/home/hm-user/.config/powerdevilrc' .*--key DimDisplayIdleTimeoutSec -- -1"
   '';
 }