diff --git a/content/treestyletab/treestyletabbrowser.js b/content/treestyletab/treestyletabbrowser.js
index e64e1f88..83a6438e 100644
--- a/content/treestyletab/treestyletabbrowser.js
+++ b/content/treestyletab/treestyletabbrowser.js
@@ -125,6 +125,20 @@ TreeStyleTabBrowser.prototype = {
 
 		var container = document.getAnonymousElementByAttribute(b.mTabContainer, 'class', 'tabs-container');
 		if (container) container.removeAttribute('overflow');
+		window.setTimeout(function() {
+			var inner = document.getAnonymousElementByAttribute(b.mTabContainer, 'class', 'tabbrowser-arrowscrollbox');
+			if (inner) inner = document.getAnonymousElementByAttribute(inner, 'anonid', 'scrollbox');
+			if (inner) inner = document.getAnonymousNodes(inner)[0];
+			if (
+				inner &&
+				(
+					inner.boxObject.width > container.boxObject.width ||
+					inner.boxObject.height > container.boxObject.height
+				)
+				) {
+				container.setAttribute('overflow', true);
+			}
+		}, 100);
 
 		/* Closing collapsed last tree breaks selected tab.
 		   To solve this problem, I override the setter to