diff --git a/moffy-samples-gtk4-run.cabal b/moffy-samples-gtk4-run.cabal
--- a/moffy-samples-gtk4-run.cabal
+++ b/moffy-samples-gtk4-run.cabal
@@ -5,7 +5,7 @@
 -- see: https://github.com/sol/hpack
 
 name:           moffy-samples-gtk4-run
-version:        0.2.1.0
+version:        0.2.1.1
 synopsis:       Package to run moffy samples - Gtk4 version
 description:    Please see the README on GitHub at <https://github.com/YoshikuniJujo/moffy-samples-gtk4-run#readme>
 category:       Control
diff --git a/src/Control/Moffy/Samples/Run/Gtk4.hs b/src/Control/Moffy/Samples/Run/Gtk4.hs
--- a/src/Control/Moffy/Samples/Run/Gtk4.hs
+++ b/src/Control/Moffy/Samples/Run/Gtk4.hs
@@ -190,6 +190,7 @@
 	(realToFrac -> l, realToFrac -> u)
 	(realToFrac -> r, realToFrac -> d)) = do
 	cairoSetSourceRgb cr clr
+	cairoSetLineWidth cr $ realToFrac lw
 	cairoMoveTo cr l u
 	cairoLineTo cr r d
 	cairoStroke cr