There are some add-ons for Firefox that are just so useful that I find myself installing them on every machine that I use on a regular basis. These add-ons are such an integral part of my everyday workflow, that I’m not sure I’d be able to get much done without them, and I think that you’ll feel the same way once you give them a try (if you don’t already have them installed, that is!)
MeasureIt allows you to click and drag to select a rectangular area of the currently displayed webpage and be told in real-time the width and height of the selection. This is a great tool for web developers who often need to quickly determine the width and/or height of page elements.
SEO for Firefox
If you are at all concerned with SEO, and you should be, go and install this add-on right now. SEO for Firefox pulls together all kinds of useful SEO-relevant data and makes it available as inline data on your search result pages, as well as on-demand for the currently viewed page through Firefox context menus.
If you use Delicious to store your online bookmarks, this add-on is a great tool to have installed. It allows you to browse and manage your existing bookmarks, create new bookmarks, and sync bookmarks between Firefox and Delicious.
A great add-on for frequent Twitter users! TwitterBar allows you to type your message in the URL bar and post both your message and the URL for the page you are currently browsing directly to Twitter. Long URLs are automatically shortened using tinyurl.com.
Do you have any Firefox add-ons that you can’t live without? Leave a comment and tell us about them!