diff --git a/modules/browser.js b/modules/browser.js
index ab2f1e66..29a56714 100644
--- a/modules/browser.js
+++ b/modules/browser.js
@@ -5637,6 +5637,8 @@ TreeStyleTabBrowser.prototype = inherit(TreeStyleTabWindow.prototype, {
 		if (!aChild.parentNode || (aParent && !aParent.parentNode)) // do nothing for closed tab!
 			return;
 
+		log('attachTabTo: attach ', aChild._tPos, ' to '. parentTab._tPos);
+
 		aInfo = aInfo || {};
 		var newAncestors = [];
 
@@ -5817,6 +5819,8 @@ TreeStyleTabBrowser.prototype = inherit(TreeStyleTabWindow.prototype, {
 		if (!parentTab)
 			return;
 
+		log('detachTab: detach ', aChild._tPos, ' from '. parentTab._tPos);
+
 		if (!aInfo.dontUpdateInsertionPositionInfo)
 			this.closeUpInsertionPositionInfoAround(aChild);