bookmarks bar rendered in wrong place in Firefox 36+

[GoogleCodeExporter]

In Firefox 36+, when using the Beta 105 (005) version of TabGroups Manager, 
when using the bookmarks bar, the bookmarks bar gets moved to the very top of 
the Firefox window upon Firefox restart. Clicking the Firefox "Customize" 
feature and then closing "Customize" puts the bookmarks bar back in its default 
place, below the URL bar, but users shouldn't need to click "Customize" upon 
each restart. This does not occur when not using TabGroups Manager.

What steps will reproduce the problem?
1. Start Firefox 36.0 with TabGroups Beta 105 (005) enabled and the bookmarks 
bar visible.
2. Watch as the bookmarks bar is placed at the top of the Firefox window.

What is the expected output? What do you see instead?
The bookmarks bar should be placed where it normally goes by default, 
underneath the URL bar.

System Info:
What version of TabGroups Manager are you using?
Beta 105 (005)
What Operative System are you using? 32 or 64 bits?
Windows 8.1 Professional 64-bit
What version of Firefox are you using?
Firefox 36.0
Are you using any other tab extension like Colorfull tabs, Multiple Tab
Handler, TabMix Plus..?
None that affect tabs

Original issue reported on code.google.com by [email protected] on 3 Mar 2015 at 3:48