This page explains all of the options available in the options window of Tab Sidebar. Screenshots are for illustrative purposes and may display differently on different platforms.
To view the options go to Tools > Add-ons and then choose the Extensions section. Then select Tab Sidebar and click the Options button.
Hide the tab bar when the sidebar is open
This option allows you to hide the browser’s main tab bar when the tab sidebar is open. The tab bar will be made visible again when you close the tab sidebar.
Display navigation buttons
Displays navigation buttons for each tab similar to those on the toolbar. The buttons include stop, reload, back, forward and history.
Display page previews
It may be preferable to not display any page previews at all. When no previews are displayed the tab will shrink down and use a much smaller space.
Keep previews up to date
The continuous updating of previews can sometimes cause performance issues and may be distracting. This option allows you to turn it off. The preview will be drawn after page load and subsequently will not change unless the window is resized or an inner frame is loaded.
Always preview the start of the page
The default is to preview the page as currently viewed in the browser window which may include being scrolled down. Many pages though are more recognisable from the top of the page. This option will make the preview always show the top of the page.
The sidebar can be displayed in a number of screen positions. The Top and Bottom positions give horizontally scrolling sets of tabs much like the normal tab bar. Left and Right positions a vertical set of tabs at either side of the webpage.
The Sidebar position places the bar in the same place that the History and Bookmarks sidebars appear. Only one of these will be displayed at a time. This can be more useful than the Left position if you use the other sidebars a lot as it saves space when you have them open.