How do I get rid of this and this ?

[max2]

> https://i.imgur.com/SVHJUWf.jpg

Or at least hide it?

[Gingerbread Man]

Enter about:debugging into the location bar to find out the Internal UUID for Tree Style Tab.

This goes in userChrome.css:

Code: Select all

/* Tree Style Tab: hide the header */
#sidebar-box[sidebarcommand^="treestyletab"] > #sidebar-header {
  display: none !important;
}

This goes in userContent.css:

Code: Select all

/* Tree Style Tab: hide the New Tab button */
@-moz-document url("moz-extension://GET THE INTERNAL UUID FROM ABOUT:DEBUGGING/sidebar/sidebar.html") {
  .newtab-button-box { display: none !important; }
}