Firefox through the eyes of the developer

Who among us uses Firefox? For example, as a developer, I realized that Firefox is more compatible with standards than Internet Explorer. Another important factor is that, for Firefox, there is just a bunch of add-ons. Some additions from the must have section have already been written here. Today is the next portion!

Fire FTP - Secure FTP client that allows you to easily and conveniently upload files to a website.
LORI - Life of Request Info - This add-on will tell you how long the current page has been loading, which will optimize the download speed.
Adblock Plus - Allows you to get rid of annoying pop-up advertising windows, and as a result - faster surfing.
ColorZilla - Did you like any color on the site? Then this addition will allow you to choose this color and convert to 16ric format or RGB.
IE Tab - Why use Internet Explorer when you can use it in Firefox. Ideal for developers to check the functionality of the site.
Measure It - Measure how big the item is on the screen.
Screen Grab - Allows you to make screenshots of the entire site, instead of taking a snapshot of only the area visible in the browser and allows you to save these screenshots in PNG and JPG.
HTML Validator - Notifies you of errors in your HTML, if any.
Firebug is the most powerful debugger for Firefox, I think it needs no introduction. Itself has many additions.
And finally, I almost forgot, supplement No. 1, which I use and will use it:
Web Developer - Add a menu and toolbar with a huge number of tools for web developers.
There are many add-ons that appear almost every day, some of which I even heard and did not see, but you can get a complete list by visiting the site .
Now, you know the list of add-ons that I use in development almost every day, and now - what do you use?

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