Firefox is among the most useful of tools to web developers. Not only for viewing web pages you create on an alternative web browser, but also due to the plethora of add-ons available for it. Foremost among these add-ons is Firebug, a feature that presents a GUI for drilling through any web page and viewing the CSS, HTML and Script.

Firebug in use...
How to get Firebug
Get Firebug by following these simple steps;
1) In Firefox's menu go to Tools -> Add-ons
2) In the Add-ons dialog click "Get Add-ons" on the toolbar
3) Type "firebug" into the search box
4) Expand Firebug in the results list and click the "Add to Firefox..." button.
NOTE: If Firebug isn't listed when the results appear click on the "See all results" link at the bottom of the results list. This will take you to the full results listing where you will be able to add the add-on to Firefox.
Using Firebug...
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