diff --git a/content/treestyletab/treestyletab.css b/content/treestyletab/treestyletab.css
index 62562a38..7f965ec2 100644
--- a/content/treestyletab/treestyletab.css
+++ b/content/treestyletab/treestyletab.css
@@ -116,3 +116,11 @@ image.tab-icon {
 tabbrowser .tabs-newbutton {
 	max-width: none !important;
 }
+
+/* for All-in-One Sidebar */
+#aiostbx-tableft-toolbox:not([incustomisemode="true"]) > toolbar[currentset="__empty"],
+#aiostbx-tableft-toolbox:not([incustomisemode="true"]) > toolbar:not([currentset]),
+#aiostbx-tabright-toolbox:not([incustomisemode="true"]) > toolbar[currentset="__empty"],
+#aiostbx-tabright-toolbox:not([incustomisemode="true"]) > toolbar:not([currentset]) {
+	visibility: collapse;
+}
diff --git a/content/treestyletab/treestyletabbrowser.js b/content/treestyletab/treestyletabbrowser.js
index 57d46d9a..a068288d 100644
--- a/content/treestyletab/treestyletabbrowser.js
+++ b/content/treestyletab/treestyletabbrowser.js
@@ -548,6 +548,10 @@ TreeStyleTabBrowser.prototype = {
 		var newTabBox = document.getAnonymousElementByAttribute(b.mTabContainer, 'id', 'tabs-newbutton-box');
 		var tabBarMode = this.getPref('extensions.tabmix.tabBarMode');
 
+		// All-in-One Sidebar
+		var toolboxContainer = document.getAnonymousElementByAttribute(b.mStrip, 'anonid', 'aiostbx-toolbox-tableft');
+		if (toolboxContainer) toolboxContainer = toolboxContainer.parentNode;
+
 		this.tabbarResizing = false;
 
 		if (pos & this.kTABBAR_VERTICAL) {
@@ -577,6 +581,9 @@ TreeStyleTabBrowser.prototype = {
 					this.setPref('extensions.tabmix.tabBarMode', 1);
 			}
 
+			if (toolboxContainer)
+				toolboxContainer.orient = 'vertical';
+
 			b.mStrip.removeAttribute('width');
 			b.mStrip.setAttribute('width', this.getTreePref('tabbar.width'));
 
@@ -641,6 +648,9 @@ TreeStyleTabBrowser.prototype = {
 				newTabBox.orient = 'vertical';
 			}
 
+			if (toolboxContainer)
+				toolboxContainer.orient = 'horizontal';
+
 			b.mStrip.removeAttribute('width');
 			b.mPanelContainer.removeAttribute('width');