I just got a new laptop, which is a good chance to start over with a clean system configuration. After trying to use FireFox without any of my normal plugins, I realized how much I’ve come to rely on these plugins:
ColorZilla: Adds a button the the bottom left of the status bar. When you click on it, you can then highlight anywhere on the page to get the HTML Color value.
FasterFox: A couple very handy utilities for timing page loads, and speeding them up in general. I find myself watching the page load timer all of the time. It simply displays the amount of time that each page takes to load in the status bar. It has a few advanced options to preload links on pages, to increase the number of simultaneous HTTP requests to a server that makes your browsing experience faster.
FireBug: Modify HTML and CSS in real time – incredibly handle for HTML development work and debugging
Google Toolbar: My main point in using this is just to see the PageRank of each page.
MeasureIt: Adds an icon to your status bar that, when clicked, turns your cursor into a crosshair so that you can measure the size of any elements on your current web page.
no-referrer: Adds an option on the context menu for links to open the link in the new tab without passing the HTTP Referrer field. I use this when on any ‘private’ pages like my awstats pages, or blog admin pages, where I don’t want to tell the world about via the HTTP referrer.
ShowIP: Adds an item to the status bar with the IP Address of the server – This is very useful information to have when doing system administration tasks. May not always be correct when changing DNS entries though. That is probably Firefox caching though instead of this plugin’s.
Web Developer: Adds all kinds of options for looking at some HTML details. The main one I use is for looking at the HTTP Response headers.