How to hide top tab bar and sidebar header?
===========================================

Due to restrictions of WebExtensions, Tree Style Tab cannot control Firefox's
top tab bar and the sidebar header. If you need to control them, see
customization examples by userChrome.css::

https://github.com/piroor/treestyletab/wiki/Code-snippets-for-custom-style-rules#for-userchromecss

But note that it is very low level customization, thus there is no guarantee
and it can cause troubles on future versions of Firefox. Please try it at your
own risk, only when you know what you are doing and if you are confident that
you can resolve such troubles by yourself.

Hiding the close tab and new tab buttons
========================================

Go to about:addons and click Preferences for Tree Style Tab. Scroll down to
Advanced -> Extra style rules for sidebar contents, then enter::

    .newtab-button-box { display: none; }
    #tabbar { bottom: 0 !important; /* Eliminate dead space on bottom */ }
    .tab .closebox { display: none; }

More examples at https://github.com/piroor/treestyletab/wiki/Code-snippets-for-custom-style-rules#for-version-2x
