diff --git a/content/treestyletab/hacks.js b/content/treestyletab/hacks.js
index e3bc720d..cb162c26 100644
--- a/content/treestyletab/hacks.js
+++ b/content/treestyletab/hacks.js
@@ -563,13 +563,23 @@ TreeStyleTabService.overrideExtensionsOnInitAfter = function() {
 		window.addEventListener('unload', listener, false);
 	}
 
-	// FLST
+	// FLST (Focus Last Selected Tab)
+	// https://addons.mozilla.org/ja/firefox/addon/32
 	if ('flst' in window) {
 		TreeStyleTabService.registerTabFocusAllowance(function(aTabBrowser) {
 			return !aTabBrowser.treeStyleTab.getPref('extensions.flst.enabled');
 		});
 	}
 
+	// Focus Last Selected Tab 0.9.5.x
+	// http://www.gozer.org/mozilla/extensions/
+	if (window['piro.sakura.ne.jp'].extensions.isInstalled('focuslastselectedtab@gozer.org') &&
+		window['piro.sakura.ne.jp'].extensions.isEnabled('focuslastselectedtab@gozer.org')) {
+		TreeStyleTabService.registerTabFocusAllowance(function(aTabBrowser) {
+			return !aTabBrowser.selectedTab.hasAttribute('lastselected');
+		});
+	}
+
 	// FireGestures
 	if ('FireGestures' in window) {
 		eval('FireGestures.onExtraGesture = '+
diff --git a/content/treestyletab/res/extensions.js b/content/treestyletab/res/extensions.js
new file mode 100644
index 00000000..0074728d
--- /dev/null
+++ b/content/treestyletab/res/extensions.js
@@ -0,0 +1,110 @@
+/*
+ Extensions Compatibility Library
+
+ Usage:
+   if (window['piro.sakura.ne.jp'].extensions.isInstalled('my.extension.id@example.com') &&
+       window['piro.sakura.ne.jp'].extensions.isEnabled('my.extension.id@example.com'))
+       window['piro.sakura.ne.jp'].extensions.goToOptions('my.extension.id@example.com');
+
+ lisence: The MIT License, Copyright (c) 2009 SHIMODA "Piro" Hiroshi
+   http://www.cozmixng.org/repos/piro/fx3-compatibility-lib/trunk/license.txt
+ original:
+   http://www.cozmixng.org/repos/piro/fx3-compatibility-lib/trunk/extensions.js
+*/
+(function() {
+	const currentRevision = 1;
+
+	if (!('piro.sakura.ne.jp' in window)) window['piro.sakura.ne.jp'] = {};
+
+	var loadedRevision = 'extensions' in window['piro.sakura.ne.jp'] ?
+			window['piro.sakura.ne.jp'].extensions.revision :
+			0 ;
+	if (loadedRevision && loadedRevision > currentRevision) {
+		return;
+	}
+
+	window['piro.sakura.ne.jp'].extensions = {
+		revision : currentRevision,
+
+		ExtensionManager : Components.classes['@mozilla.org/extensions/manager;1']
+			.getService(Components.interfaces.nsIExtensionManager),
+		RDF : Components.classes['@mozilla.org/rdf/rdf-service;1']
+			.getService(Components.interfaces.nsIRDFService),
+		WindowMediator : Components.classes['@mozilla.org/appshell/window-mediator;1']
+			.getService(Components.interfaces.nsIWindowMediator),
+		Prefs : Components.classes['@mozilla.org/preferences;1']
+			.getService(Components.interfaces.nsIPrefBranch),
+
+		isInstalled : function(aId)
+		{
+			return this.ExtensionManager.getInstallLocation(aId);
+		},
+
+		isEnabled : function(aId)
+		{
+			var res  = this.RDF.GetResource('urn:mozilla:item:'+aId);
+			var appDisabled = false;
+			try {
+				appDisabled = this.ExtensionManager.datasource.GetTarget(
+						res,
+						this.RDF.GetResource('http://www.mozilla.org/2004/em-rdf#appDisabled'),
+						true
+					).QueryInterface(Components.interfaces.nsIRDFLiteral)
+					.Value == 'true';
+			}
+			catch(e) {
+			}
+			var userDisabled = false;
+			try {
+				userDisabled = this.ExtensionManager.datasource.GetTarget(
+						res,
+						this.RDF.GetResource('http://www.mozilla.org/2004/em-rdf#userDisabled'),
+						true
+					).QueryInterface(Components.interfaces.nsIRDFLiteral)
+					.Value == 'true';
+			}
+			catch(e) {
+			}
+
+			return !appDisabled && !userDisabled;
+		},
+
+		goToOptions : function(aId)
+		{
+			var res  = this.RDF.GetResource('urn:mozilla:item:'+aId);
+			var uri;
+			try {
+				uri = this.ExtensionManager.datasource.GetTarget(
+						res,
+						this.RDF.GetResource('http://www.mozilla.org/2004/em-rdf#optionsURL'),
+						true
+					).QueryInterface(Components.interfaces.nsIRDFLiteral)
+					.Value;
+			}
+			catch(e) {
+			}
+			if (!uri) return;
+
+			var windows = this.WindowMediator.getEnumerator(null);
+			while (windows.hasMoreElements())
+			{
+				let win = windows.getNext();
+				if (win.location.href == uri) {
+					win.focus();
+					return;
+				}
+			}
+			var instantApply = false;
+			try {
+				instantApply = this.Prefs.getBoolPref('browser.preferences.instantApply');
+			}
+			catch(e) {
+			}
+			window.openDialog(
+				uri,
+				'',
+				'chrome,titlebar,toolbar,centerscreen,' + (instantApply ? 'dialog=no' : 'modal' )
+			);
+		}
+	};
+})();
diff --git a/content/treestyletab/treestyletab.xul b/content/treestyletab/treestyletab.xul
index 23b90794..55a52861 100644
--- a/content/treestyletab/treestyletab.xul
+++ b/content/treestyletab/treestyletab.xul
@@ -12,6 +12,7 @@
 <script src="res/boxObject.js" type="application/x-javascript; version=1.7"/>
 <script src="res/autoScroll.js" type="application/x-javascript; version=1.7"/>
 <script src="res/animationManager.js" type="application/x-javascript; version=1.7"/>
+<script src="res/extensions.js" type="application/x-javascript; version=1.7"/>
 <script src="treestyletab.js" type="application/x-javascript; version=1.7"/>
 <script src="treestyletabbrowser.js" type="application/x-javascript; version=1.7"/>
 <script src="preloadImages.js" type="application/x-javascript; version=1.7"/>