So I’ve already pointed out features of Firefox 2 like tabbed browsing and detailed configuration. As you may have noticed Firefox 2 now features a Close button (that little X) for individual tabs. This is unlike in Firefox 1.X where a solo Close button is located at the right end of the tabs.
Here’s a cool tweak on modifying how the tab Close button behaves:
- Bring up the in-depth configuration with about:config
- In the “Filter” field type browser.tabs.closeButtons
- Double-click on the entry and enter a number below:
0 – Display tab Close button only on the active tab
1 – Display tab Close button on each tab (default)
2 – No tab Close buttons will be displayed
3 – Display a single close button at the end of the tab bar (a la Firefox 1.X)
- Click OK.
- Close the configuration tab or window.
Source: Firefox 2.0 Close Tab Buttons