Using the very helpful Toolbar Buttons Firefox plugin, you can add more than 70 ‘new’ buttons to your Firefox Toolbar.

1. To get started, install Toolbar Buttons as you would any other Firefox plugin. And like all plugins, you’ll need to restart Firefox before you can use it.
2. Once Firefox has restarted, select View -> Toolbars -> Customize..

   
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3. From here you can drag any of the 70+ buttons to your Toolbar. For a full description of what each button does, see this page.


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4. As shown in the screenshot below, some of my favorite buttons are Reload skip cache (which reloads the current page without using the cache – easier to click this button than hold down shift and click the normal reload), Quick Bookmark (self-explanatory) and Reopen the last closed tab – because I accidentally close tabs at least 20 times a day.

   

5. When you’re done adding buttons, just close the Customize Toolbar window.