diff --git a/content/treestyletab/treestyletab.js b/content/treestyletab/treestyletab.js
index 6dc4273c..1581841f 100644
--- a/content/treestyletab/treestyletab.js
+++ b/content/treestyletab/treestyletab.js
@@ -13,6 +13,7 @@ var TreeStyleTabService = {
 	kVERTICAL          : 'treestyletab-vertical',
 	kINVERTED          : 'treestyletab-appearance-inverted',
 	kSTYLE             : 'treestyletab-style',
+	kFIRSTTAB_BORDER   : 'treestyletab-firsttab-border',
 
 	kTWISTY                : 'treestyletab-twisty',
 	kTWISTY_CONTAINER      : 'treestyletab-twisty-container',
@@ -682,6 +683,7 @@ catch(e) {
 
 		aTabBrowser.__treestyletab__observer = new TreeStyleTabBrowserObserver(aTabBrowser);
 		aTabBrowser.__treestyletab__observer.observe(null, 'nsPref:changed', 'extensions.treestyletab.tabbar.style');
+		aTabBrowser.__treestyletab__observer.observe(null, 'nsPref:changed', 'extensions.treestyletab.showBorderForFirstTab');
 
 		delete addTabMethod;
 		delete removeTabMethod;
@@ -2484,6 +2486,14 @@ TreeStyleTabBrowserObserver.prototype = {
 
 					case 'extensions.treestyletab.tabbar.style':
 						this.mTabBrowser.setAttribute(TreeStyleTabService.kSTYLE, value);
+						break;
+
+					case 'extensions.treestyletab.showBorderForFirstTab':
+						if (value)
+							this.mTabBrowser.setAttribute(TreeStyleTabService.kFIRSTTAB_BORDER, true);
+						else
+							this.mTabBrowser.removeAttribute(TreeStyleTabService.kFIRSTTAB_BORDER);
+						break;
 
 					default:
 						break;
diff --git a/defaults/preferences/treestyletab.js b/defaults/preferences/treestyletab.js
index face1437..4d60bf78 100644
--- a/defaults/preferences/treestyletab.js
+++ b/defaults/preferences/treestyletab.js
@@ -4,6 +4,7 @@ pref("extensions.treestyletab.tabbar.invertUI",       true);
 pref("extensions.treestyletab.tabbar.scroll.smooth",  true);
 pref("extensions.treestyletab.tabbar.scroll.timeout", 250);
 pref("extensions.treestyletab.tabbar.style",          "mixed");
+pref("extensions.treestyletab.showBorderForFirstTab", false);
 pref("extensions.treestyletab.levelMargin",           12);
 
 pref("extensions.treestyletab.show.openSelectionLinks", true);
diff --git a/skin/classic/treestyletab/treestyletab.css b/skin/classic/treestyletab/treestyletab.css
index e0b8b69d..08f7a0ab 100644
--- a/skin/classic/treestyletab/treestyletab.css
+++ b/skin/classic/treestyletab/treestyletab.css
@@ -28,6 +28,9 @@ tabbrowser[treestyletab-vertical="true"] .tabbrowser-tab {
 	-moz-border-radius-bottomright : 0 !important;
 	-moz-box-align: stretch !important;
 }
+tabbrowser[treestyletab-vertical="true"][treestyletab-firsttab-border="true"] .tabbrowser-tab:first-child {
+	-moz-border-top-colors: ThreeDShadow ThreeDFace !important;
+}
 tabbrowser[treestyletab-vertical="true"] .tabbrowser-tab[selected="true"] {
 	margin: 0 !important;
 	padding: 0 0.2em !important;
@@ -35,6 +38,9 @@ tabbrowser[treestyletab-vertical="true"] .tabbrowser-tab[selected="true"] {
 	-moz-border-top-colors: ThreeDHighlight ThreeDHighlight !important;
 	-moz-border-bottom-colors: ThreeDShadow ThreeDHighlight !important;
 }
+tabbrowser[treestyletab-vertical="true"][treestyletab-firsttab-border="true"] .tabbrowser-tab:first-child[selected="true"] {
+	-moz-border-top-colors: ThreeDShadow ThreeDHighlight !important;
+}
 
 tabbrowser[treestyletab-vertical="true"] .tabbrowser-tab > .tab-image-left,
 tabbrowser[treestyletab-vertical="true"] .tabbrowser-tab > .tab-image-right {
@@ -135,11 +141,17 @@ tabbrowser[treestyletab-vertical="true"][treestyletab-style="mixed"] .tabbrowser
 	-moz-border-top-colors: #e0e8f6 #e0e8f6 !important;
 	-moz-border-bottom-colors: ThreeDShadow #e0e8f6 !important;
 }
+tabbrowser[treestyletab-vertical="true"][treestyletab-style="mixed"][treestyletab-firsttab-border="true"] .tabbrowser-tab:first-child:hover {
+	-moz-border-top-colors: ThreeDShadow #e0e8f6 !important;
+}
 tabbrowser[treestyletab-vertical="true"][treestyletab-style="mixed"] .tabbrowser-tab[selected="true"] {
 	background: #c1d2ee !important;
 	-moz-border-top-colors: #c1d2ee #c1d2ee !important;
 	-moz-border-bottom-colors: ThreeDShadow #c1d2ee !important;
 }
+tabbrowser[treestyletab-vertical="true"][treestyletab-style="mixed"][treestyletab-firsttab-border="true"] .tabbrowser-tab:first-child[selected="true"] {
+	-moz-border-top-colors: ThreeDShadow #c1d2ee !important;
+}
 
 tabbrowser[treestyletab-vertical="true"][treestyletab-style="mixed"] .tabbrowser-tab:hover,
 tabbrowser[treestyletab-vertical="true"][treestyletab-appearance-inverted="true"][treestyletab-style="mixed"] .tabbrowser-tab:hover {
@@ -209,7 +221,8 @@ tabbrowser[treestyletab-vertical="true"] tab[treestyletab-drop-position="self"]
 	list-style-image: url("dropmarker-right.png");
 }
 */
-tabbrowser[treestyletab-vertical="true"] tab[treestyletab-drop-position="self"] {
+tabbrowser[treestyletab-vertical="true"] tab[treestyletab-drop-position="self"],
+tabbrowser[treestyletab-vertical="true"][treestyletab-firsttab-border="true"] tab:first-child[treestyletab-drop-position="self"] {
 	-moz-border-top-colors: -moz-dialogtext -moz-dialogtext !important;
 	-moz-border-right-colors: -moz-dialogtext -moz-dialogtext !important;
 	-moz-border-bottom-colors: -moz-dialogtext -moz-dialogtext !important;
@@ -221,7 +234,8 @@ tabbrowser[treestyletab-vertical="true"] tab[treestyletab-drop-position="before"
 	list-style-image: url("dropmarker-up.png");
 }
 */
-tabbrowser[treestyletab-vertical="true"] tab[treestyletab-drop-position="before"] {
+tabbrowser[treestyletab-vertical="true"] tab[treestyletab-drop-position="before"],
+tabbrowser[treestyletab-vertical="true"][treestyletab-firsttab-border="true"] tab:first-child[treestyletab-drop-position="before"] {
 	-moz-border-top-colors: -moz-dialogtext -moz-dialogtext !important;
 }