[Couldn't Reproduce] - New version(2.8.8) conflict with tree sytle tab

What steps will reproduce the problem?
1.Install tree style tab 
here(https://addons.mozilla.org/zh-CN/firefox/addon/tree-style-tab/)
2.open many tabs,upto the screen height

What is the expected output?
the new tab botton still in the area
What do you see instead?
the new tab botton extend beyond the area

What version of "Hide Caption Titlebar Plus" addon are you using?
2.88
What version of Firefox?
34.0.5
On what operating system?
Win 8.1 x64

- Please provide any additional information below.

- Please provide your system info by using this url (with installed hct+):
chrome://hidecaptionplus/content/system_info.html  (can be copy/pasted as
text also)
Name of the browser (appName)   Netscape
Name of the browser vendor (vendor) 
Code name of the browser (appCodeName)  Mozilla
Engine of the browser (product) Gecko
Build number of the browser engine (productSub) 20100101
Version and platform of the browser (appVersion)    5.0 (Windows)
Version of the browser given by the vendor (vendorSub)  
Build identifier of the browser (buildID)   20141126041045
User-agent request header (userAgent)   Mozilla/5.0 (Windows NT 6.3; WOW64; 
rv:34.0) Gecko/20100101 Firefox/34.0
Language of the browser (chrome-locale) zh-CN
Language preference in the browser (useragent-locale)   zh-CN
Cookies are enabled (cookieEnabled) true
Operating system (platform) Win32
Information about the OS and CPU (oscpu)    Windows NT 6.3; WOW64
System is online (onLine)   true

- If there are visual issues, please provide also screenshot/s (preferred
uploaded here instead of external link)

Original issue reported on code.google.com by sqh1...@gmail.com on 13 Dec 2014 at 6:36

Attachments:

12.png

skyleet / firefox-hide-caption-titlebar-plus

[Couldn't Reproduce] - New version(2.8.8) conflict with tree sytle tab #267