diff --git a/Packages/jp.suzuryg.face-emo/Editor/Detail/View/ExpressionEditor/ExpressionPreviewWindow.cs b/Packages/jp.suzuryg.face-emo/Editor/Detail/View/ExpressionEditor/ExpressionPreviewWindow.cs
index 969cb3ba..31777aa7 100644
--- a/Packages/jp.suzuryg.face-emo/Editor/Detail/View/ExpressionEditor/ExpressionPreviewWindow.cs
+++ b/Packages/jp.suzuryg.face-emo/Editor/Detail/View/ExpressionEditor/ExpressionPreviewWindow.cs
@@ -18,9 +18,13 @@ public bool IsDocked
         {
             get
             {
+#if UNITY_2019
                 BindingFlags flags = BindingFlags.NonPublic | BindingFlags.Instance;
                 MethodInfo method = GetType().GetProperty( "docked", flags ).GetGetMethod( true );
                 return (bool)method.Invoke( this, null );
+#else
+                return docked;
+#endif
             }
         }
 
diff --git a/Packages/jp.suzuryg.face-emo/Editor/Detail/View/SubWindowBase.cs b/Packages/jp.suzuryg.face-emo/Editor/Detail/View/SubWindowBase.cs
index 163cfee5..9064aad2 100644
--- a/Packages/jp.suzuryg.face-emo/Editor/Detail/View/SubWindowBase.cs
+++ b/Packages/jp.suzuryg.face-emo/Editor/Detail/View/SubWindowBase.cs
@@ -11,9 +11,13 @@ public bool IsDocked
         {
             get
             {
+#if UNITY_2019
                 BindingFlags flags = BindingFlags.NonPublic | BindingFlags.Instance;
                 MethodInfo method = GetType().GetProperty( "docked", flags ).GetGetMethod( true );
                 return (bool)method.Invoke( this, null );
+#else
+                return docked;
+#endif
             }
         }