Tabbed browsing allows you to load multiple Web sites in a single window. To switch between pages in use, use the tabs at the top of the window. If you often use more than one Web page at a time, tabbed browsing makes it easier to switch between pages.
Opening Tabs
To open a new tab, from the menu bar, select File › New Tab or press Ctrl–T. This opens an empty tab in the Firefox window. To open a link on a Web page or a bookmark in a tab, middle-click it. Alternatively, right-click a link and select Open Link in New Tab. You may also open an address in the location bar in a new tab with a middle-click or by pressing Ctrl–Enter.
Closing Tabs
Right-click a tab to open a context menu, giving you access to tab managing options such as closing, reloading, or bookmarking. To close a tab, you may also use Ctrl–W or click the close button. Any closed tab can be restored by choosing from the menu bar, History › Recently Closed Tabs. To reopen the last closed tab, either choose Undo Close Tab from the context menu or press Ctrl–Shift–T.
Sorting Tabs
By default, tabs are sorted in the order you opened them. Rearrange the tab order by dragging and dropping a tab to the desired position. If you have opened a large number of tabs, they cannot all be displayed in the tab bar at the same time. Use the arrows at the ends of the bar to move left or right-click the down arrow at the right end of the tab bar to get a list of all tabs.
Dragging and Dropping
Drag and drop also works with tabs. Drag a link onto an existing tab to open it in that tab or drag and drop a link on an empty space in the tab bar to open a new tab. Drag and drop a tab outside of the tab bar to open it in a new browser window.