diff --git a/Assets/Plugins/UniRx/Scripts/UnityEngineBridge/MainThreadDispatcher.cs b/Assets/Plugins/UniRx/Scripts/UnityEngineBridge/MainThreadDispatcher.cs
index 91cc8c45..baf26d2b 100644
--- a/Assets/Plugins/UniRx/Scripts/UnityEngineBridge/MainThreadDispatcher.cs
+++ b/Assets/Plugins/UniRx/Scripts/UnityEngineBridge/MainThreadDispatcher.cs
@@ -449,7 +449,11 @@ public static void Initialize()
 
                 try
                 {
+#if UNITY_2020_3_OR_NEWER
+                    dispatcher = GameObject.FindAnyObjectByType<MainThreadDispatcher>();
+#else
                     dispatcher = GameObject.FindObjectOfType<MainThreadDispatcher>();
+#endif
                 }
                 catch
                 {
@@ -577,7 +581,11 @@ static void DestroyDispatcher(MainThreadDispatcher aDispatcher)
 
         public static void CullAllExcessDispatchers()
         {
+#if UNITY_2020_3_OR_NEWER
+            var dispatchers = GameObject.FindObjectsByType<MainThreadDispatcher>(FindObjectsSortMode.None);
+#else
             var dispatchers = GameObject.FindObjectsOfType<MainThreadDispatcher>();
+#endif
             for (int i = 0; i < dispatchers.Length; i++)
             {
                 DestroyDispatcher(dispatchers[i]);
@@ -588,7 +596,11 @@ void OnDestroy()
         {
             if (instance == this)
             {
+#if UNITY_2020_3_OR_NEWER
+                instance = GameObject.FindAnyObjectByType<MainThreadDispatcher>();
+#else
                 instance = GameObject.FindObjectOfType<MainThreadDispatcher>();
+#endif
                 initialized = instance != null;
 
                 /*
diff --git a/Assets/RuntimeUnitTestToolkit/Editor/UnitTestBuilder.MenuItems.cs b/Assets/RuntimeUnitTestToolkit/Editor/UnitTestBuilder.MenuItems.cs
index 9ec1c545..af1785d5 100644
--- a/Assets/RuntimeUnitTestToolkit/Editor/UnitTestBuilder.MenuItems.cs
+++ b/Assets/RuntimeUnitTestToolkit/Editor/UnitTestBuilder.MenuItems.cs
@@ -169,6 +169,7 @@ static void BuildTargetStandaloneWindows64()
         SaveSettings(settings);
     }
 
+#if !UNITY_2019_2_OR_NEWER
     [MenuItem("Test/Settings/BuildTarget/StandaloneLinux", validate = true, priority = 3)]
     static bool ValidateBuildTargetStandaloneLinux()
     {
@@ -184,6 +185,7 @@ static void BuildTargetStandaloneLinux()
         settings.BuildTarget = BuildTarget.StandaloneLinux;
         SaveSettings(settings);
     }
+#endif
 
     [MenuItem("Test/Settings/BuildTarget/StandaloneLinux64", validate = true, priority = 4)]
     static bool ValidateBuildTargetStandaloneLinux64()
diff --git a/Assets/RuntimeUnitTestToolkit/Editor/UnitTestBuilder.cs b/Assets/RuntimeUnitTestToolkit/Editor/UnitTestBuilder.cs
index 8ca10687..10095538 100644
--- a/Assets/RuntimeUnitTestToolkit/Editor/UnitTestBuilder.cs
+++ b/Assets/RuntimeUnitTestToolkit/Editor/UnitTestBuilder.cs
@@ -113,7 +113,11 @@ public static void BuildUnitTest()
         }
         if (settings.UseCurrentScriptBackend)
         {
+#if UNITY_2021_2_OR_NEWER
+            settings.ScriptBackend = PlayerSettings.GetScriptingBackend(UnityEditor.Build.NamedBuildTarget.FromBuildTargetGroup(ToBuildTargetGroup(settings.BuildTarget)));
+#else
             settings.ScriptBackend = PlayerSettings.GetScriptingBackend(ToBuildTargetGroup(settings.BuildTarget));
+#endif
         }
 
         if (buildPath == null)
@@ -386,17 +390,27 @@ static void Build(string sceneName, string buildPath, RuntimeUnitTestSettings se
         {
             options |= BuildOptions.AutoRunPlayer;
         }
+#if !UNITY_2021_2_OR_NEWER
         if (settings.Headless)
         {
             options |= BuildOptions.EnableHeadlessMode;
         }
+#endif
 
         var targetGroup = ToBuildTargetGroup(settings.BuildTarget);
+#if UNITY_2021_2_OR_NEWER
+        var currentBackend = PlayerSettings.GetScriptingBackend(UnityEditor.Build.NamedBuildTarget.FromBuildTargetGroup(targetGroup));
+#else
         var currentBackend = PlayerSettings.GetScriptingBackend(targetGroup);
+#endif
         if (currentBackend != settings.ScriptBackend)
         {
             UnityEngine.Debug.Log("Modify ScriptBackend to " + settings.ScriptBackend);
+#if UNITY_2021_2_OR_NEWER
+            PlayerSettings.SetScriptingBackend(UnityEditor.Build.NamedBuildTarget.FromBuildTargetGroup(targetGroup), settings.ScriptBackend);
+#else
             PlayerSettings.SetScriptingBackend(targetGroup, settings.ScriptBackend);
+#endif
         }
 
         var buildOptions = new BuildPlayerOptions
@@ -407,6 +421,12 @@ static void Build(string sceneName, string buildPath, RuntimeUnitTestSettings se
             scenes = new[] { sceneName },
             locationPathName = buildPath
         };
+#if UNITY_2021_2_OR_NEWER
+        if (settings.Headless)
+        {
+            buildOptions.subtarget = (int)StandaloneBuildSubtarget.Server;
+        }
+#endif
 
         UnityEngine.Debug.Log("UnitTest Build Start, " + settings.ToString());
 
@@ -415,7 +435,11 @@ static void Build(string sceneName, string buildPath, RuntimeUnitTestSettings se
         if (currentBackend != settings.ScriptBackend)
         {
             UnityEngine.Debug.Log("Restore ScriptBackend to " + currentBackend);
+#if UNITY_2021_2_OR_NEWER
+            PlayerSettings.SetScriptingBackend(UnityEditor.Build.NamedBuildTarget.FromBuildTargetGroup(targetGroup), currentBackend);
+#else
             PlayerSettings.SetScriptingBackend(targetGroup, currentBackend);
+#endif
         }
 
         if (buildReport.summary.result != BuildResult.Succeeded)